In the third of a six-part series entitled Age of Empire, the BBC's Jonathan Marcus examines some of the issues confronting the US army in an age of the pre-emptive strike.
The US Defence Secretary Donald Rumsfeld is not an easy man to pin down.
He prefers what his staff see as more efficient "round-table" sessions with journalists rather than "one-on-one" interviews.
Mr Rumsfeld is a man who is noted for giving answers of such convoluted syntax that a book of poems has even been published in his honour.
But at the Nato defence ministers meeting in Colorado Springs last October, he did give a serious answer to a serious question.
When asked whether the whole experience in Iraq suggested that the US Army is badly over-stretched, there was no way he would agree.
The generals had not asked for more troops, he said, the problem was not manpower.
Well, just a few months later the Pentagon announced a "temporary" increase in the size of the US Army.
Some 30,000 additional soldiers are to be added to its strength.
Mr Rumsfeld does not agree that the US army is over-stretched
But as the noted defence analyst and commentator Tony Cordesman told me, numbers are not everything.
"The idea that more is better," he said, "is not easy to contradict, but it is not clear that it has solved the problems of asymmetric warfare".
Asymmetric warfare is the buzz phrase of the moment, and the terror attacks of 9/11 were in one sense a form of it.
So too is the underground guerrilla campaign being waged against US and other foreign forces in Iraq.
The idea is that the United States is now so strong that nobody in their right mind would take on a US armoured division - the Iraq war was graphic proof of that.
But the problem for the Pentagon is that as the world's dominant superpower the US has to maintain a whole range of forces and capabilities.
It must be able to fight counter-insurgency operations at one end of the scale but maintain its edge in high-intensity combat at the other.
Resources are finite, so the key thing is to make the military more deployable and ensure that the military's structure is flexible enough to put together different force packages for different operations.
A new armoured vehicle called Stryker will eventually equip six new brigades and is very much a symbol of this process.
The idea is to create a new mobile force with sufficient punch to look after themselves on the battlefield.
The new unit has its own intelligence gathering capabilities, underlining once again that the harnessing of information is the key to military transformation.
The US wants to create a new mobile force
Stryker is just an interim solution to the problems of firepower and mobility.
It is a controversial programme, and many doubt that the vehicle provides adequate protection.
The first unit is now in Iraq, and will provide a real life test of the new brigade's potential.
Meanwhile the US army is not just being expanded but totally reorganised into a new modular structure.
In future brigades will be able to be combined together in a far more flexible pattern to tailor specific forces to specific missions.
If mobility and firepower characterise the new US army then another aspect of US military dominance is global reach.
And nothing better exemplifies this than the B-2 Spirit bomber at the Whiteman Air Force base in Missouri.
B2s can target almost anywhere in the world from the US
With air-to-air refuelling, B-2's can fly from Whiteman non-stop to virtually anywhere in the world, drop their bombs, and return home.
The B-2 was first used in combat during the air war over Kosovo.
In March 1999 two aircraft from Whiteman attacked Serbian targets in a marathon 31 hour mission.
Equipment and technology are all very well, but another thing that needs to be examined is the strategic rationale for the way in which it will all be used.
In June 2002 President George Bush seemed to announce a new doctrine of pre-emptive military action.
The idea was that the combination of the terrorist threat, weapons of mass destruction and failed states was so great that the US would need to strike as soon as a threat was identified.
For some the Iraq war represented the first application of this doctrine, though others would ague that this was seen by the White House as simply unfinished business.
The war in Iraq has highlighted one fundamental issue relating to pre-emptive war.
It is the need for reliable intelligence that accurately presents the gravity of the threat.
The Age of Empire series is broadcast on Mondays at 09:05GMT on BBC World Service Radio.
To send your views on this series, use the form at the bottom of the page.
America is an empire. But only to the extent that it can place its commercial outpost in key places. These outposts of American imperial might go by the names of McDonalds, Burger King, Pizza Hut, Starbucks among others. These outposts are everywhere (Just take a walk outside of Windsor Castle). Historically speaking, it is a pretty benign for the most part.
Jose Palacios, Miami, FL
People seem to forget the States themselves are empire. There were people living hear before the Mayflower arrived you know. It's said that when an evil rises, other nations bond as strange bedfellows to put that evil down. The USSR, Britain, and the USA did it to end Nazism. Maybe we've seen a sneak preview of another "bonding for the world's sake" via the Russian, French, and German opposition to the American Blitz in Iraq. I just hope the Europeans resolve holds out as the American people have failed to check our own extremist leaders.
Stan McPeek, Duluth, Minnesota
I find it interesting that the United States is actively involved in 140 countries. This was stated a while ago on a news cast I had been casually listening to about the CIA.
More importantly, I thought that might not be a good idea until I heard the US being beat up about our failure to provide support to Afghanistan after the Russians left.
Now, wait a minute. We are cursed for our interference around the world, but now, we are cursed for not entering another country? So, if we are damned both ways by world opinion, maybe it is better to just go it our way?
John Hastie, Darlington, WI USA
Bravo to Mr. Marcus and his very even-handed approach to a long unasked question. In my opinion, the American people aren't very informed regarding the actions of their government. Benjamin Franklin once said "We have simple solutions, what we need are simple problems," and I think those words still ring true today. America is a massive, complex entity which can no longer live in the vacuum George Washington once prescribed. Like it or not, we can't hide behind the two oceans on our borders forever. The American people need to get away from the idea that more money, more technology, and less oversight will solve their problems. I guess what's most astounding to me is the unshakable faith some Americans continue to have in their government after so many miscues, from the Bay of Pigs to the War in Iraq. It's this naive, self-blinding approach which hurts America more than any other single force. If America really is a superpower, and if it really is an Empire, it will almost certainly crumble from within, not without.
Dan Weber, Boston, Massachusetts, USA
I think more attention needs to be paid to the economic underpinnings of imperial ambitions. They say the British Empire was acquired in "a fit of absence of mind", mainly by businesses like The East India Company and the Hudson's Bay Company. Is this not also true of the United States? And having become economically dependent on a commanding position in world trade, is the development of a giant military to defend that position not inevitable? But the costs of defending an ever-expanding Empire always outweigh the benefits in the long run - witness the present American balance of trade and currency troubles. Not too different from the British, and for the same reasons. Didn't the Vietnam War kill the US gold standard, the height of the Cold War cause the 1985 dollar devaluation, and the Gulf Wars cause the current devaluation? Just like the Brits going into debt in the World Wars, eh?
Paul Connor, Toronto, Canada
Empires have existed for nearly all of human history, and there's no reason to think that the U.S. is somehow immune to this tendency. If we are to be an empire, let's have it be an empire that does more than what is good for us and us alone in the short term. We need to pay more, not less, attention to the rest of the world, and grant other peoples the respect we want to receive. That's the way to distinguish this empire. Denial is just denial.
The United States is an empire. Like the Roman Empire, the US expanded and expanded, gobbling up its neighbours until it reached a sort of geographic equilibrium between centrifugal and centrifugal tendencies. Then, like Rome, it sought to dominate other nations through a system of treaties and economic domination. And the Romans were happy with this arrangement, until one of their clients, or allies, or any weaker nation in general, got too uppity, and then it was smashed down, much in the same way the US has done to the third world, especially Latin America. So yes, the US is definitely an empire, by any definition. And I think this Bush neo-Conservative doctrine merely confirms this. However, the average American is not particularly interested in empire; all s/he wants is for the prospect of a better life for him/her and his/her children. Americans better wake up and make a choice; if you want empire and it's benefits, then you have to be willing to go along with the empire-sized problems that come with; if not, then Americans need to undergo a radical change in lifestyle and attitude. We want our cake and to eat it too, but in the long run life doesn't work that way.
Bennett, Los Angeles
America an Empire!?! The perspective that the world views America as an Empire is very ironic. Americans as a whole have no interest in ruling other lands. We're more concerned with our own lives then the rest of world (whether right or wrong). The Globe however tends to criticize the US then holds out their needy hands whenever a conflict arises. The world at every conflict looks to the US for help. I think a good story might be how the US got nominated as a scapegoat by the rest of their Global neighbours. It might be interesting if the US ever turned their back and said 'fend for yourself'.
By the way how far in left field are Californians from the rest of the US?
JS, Ohio, USA
As America controls more resources than any other country on the planet it is necessarily an imperial power. How it chooses to exercise that power is another question. Presently there is a malign administration at the wheel with thinly disguised ambitions to control Middle East energy resources and to eliminate any resistance thereof. In support the US imperial lords have an isolated, uninformed and bovine electorate to support hysterical ravings regarding 'freedom and democracy'. Imperial ambitions are only viable in the US political process under this arrangement. Once elected the emperor can do what he wants.
Robert Taylor, Pasadena, California USA
The US is probably the most benign empire in history, due to its people's reluctance to pursue an imperial policy. The US holds a significant economical and military power, which today has a global reach. This power has been rising since the end of the Civil War: the US has taken advantage of its huge natural resources, its solid social and political system, the geographical isolation and thus the absence of competing neighbours and finally over 130 years without a war fought on its territory. Inevitably, the US interests make "imperial decisions" at times, and its power makes them possible, in order to protect the security and standard of living of its citizens. But these "imperial decisions" do not amount to a classic empire. In fact, they are strongly restrained by a culture reluctant to dominate and exploit. Thus, the US governments had to justify any "imperial decision" through higher ideals, and prove them by a great deal of sharing with other nations. T
Michael Cortelletti, Ithaca, NY USA & Berlin, Germany
Certainly the US is an empire. Yes we have the elements of a militaristic empire. However the strength lies in our true empire, an economic one. I don't know that we ever set out to become an empire, rather I would say the world asked us to.
Kevin Norsen, Buffalo, New York
Somebody is going to be King of the Hill, better the Americans than the Chinese or the Germans, for lord's sake. I was personally involved in American politics, and yes I wanted power, not so I could rub someone else's face in it, but to keep them from rubbing mine! Say what you will but it can be a whole lot worse. An American will kick the devil out of you but buy you a beer afterwards.
Reed Schrichte, Ho Chi Minh City, Viet Nam
I think it's time we, Americans, admit we are imperialists. What else is it called when you litter the globe with military bases, thus bringing every nation on the planet within your military reach? Now that's influence. I'm thankful for this article, as maybe Americans might become more honest with themselves when they talk foreign policy. Then hopefully we can do something to change it.
Dan Bluemel, Hollywood, California, USA
Empire? No not really, we dominate in the economic sphere, because we have created a competitive system. This was necessary because of the vast physical size of the USA, which has given rise to literally hundreds of key industries. Most countries are small and do not have much real competition. Usually, small countries have only a few key players or industries which control everything. America has no desire to physically dominate others or occupy another country long term. Our nation is one of immigrants and they came here to get away from that.
Mark Seiler, Harrison, Ohio
Empire yes, what do we think we are when we run around (and have since our inception) the world influencing the political systems of other countries for the good of American Corporations? The good guys? I suspect it is hard for people who have never read about history outside of a public school, to fully understand what we are. We are an Empire whether we like it or not, and I suggest if you feel uncomfortable with the term do something about it, read something other than the news feed to us by big business, and vote, and be vocal.
Elizabeth Bernard, Greenfield, America
Bravo for really trying to understand what makes Americans tick and not some knee-jerk reactionary pre-drawn conclusion statements.
Ok, with that said, the US has an identity of not even wanting to deal with the rest of the world. All of the people here came to get away from the mess "over there". We have a national collective desire to be "left alone" to raise our kids and live our lives in peace. However, when someone threatens that peace, we will destroy the threat. We are also a land of fighters and winners.
Once you get the national will behind a cause, there is NO nation on earth that can stop us. We didn't start this war, but "WE will finish it!" As for empire? Only because Europe embraces socialism, has it been left behind. Look seriously at the other world players. The only three countries in the world that have a chance to be our equal are UK, India and China. The rest are either corrupt, socialist or just now beginning to industrialize.
Craig Traylor, Houston, Texas
Sorry Doug, but the US population has supported imperial ambitions for the past, oh, 200 years, I think. The US is a nation very much at home with conquest and dominance, beginning, first, with the westward "expansion" and continuing to this day through various episodes such as the Spanish-American War, World Wars I and II (which made the US a power on the European continent by setting us up in the vacuum left by Germany's defeat), and the Persian Gulf Wars (giving us imperial control over an enormous oil reserve). The US population does, indeed, support "all" such imperial ventures; however, it supports them in a state of almost pathetic denial whereby it believes it is supporting good and noble efforts ("the war to end all wars", etc.) while, in fact, it is, in reality, being misled and duped.
Chris Edmonds, Walnut Creek, California
Anyone who believes the US population would support long-term Imperial ambitions has little understanding of Americans. The vast bulk of us carry family histories replete with suffering from Imperialistic expansions of others in Europe, Asia, and elsewhere. Empire USA? No way, except perhaps in the case of the moon.
Doug Petersen, Twin Falls, Idaho USA
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