Question: I suspect being economically strong and independent aren't enough to become a super power in today world, I realised that US is slowly losing it's grip as a super power after it starts shifting focus on other research areas and staying away from making nukes. Given today technology, can a nation become a super power without having any nuclear programme? Sorry for my childish thinking but I think people would definitely listen when you can talk at over 250dB.

Answer: 
**First to achieve Lunar/Space Colony.**

Say a multibillionaire sets his sights on space exploration. Before the slow engines of states achieve similar success, his country could be lauded SuperPower if they get first De FACTO ownership of celestial bodies.

The logistical capabilities that accomplishment grants, the information available to them. 

*And the sheer Bragging Rights.*

That makes you the sole state who controls a rare commodity, akin to China holding the Lion's share of rare earths.

Remember that Politics is the Art of looking the part.
Japan might be considered a super power and they don't have nukes - by choice. Should they change their stance on nukes, they could probably develop them within one or two years.

Their power is mostly through economics, technology and military Allies which are more important in todays world.

Nowadays - at least in the western world - actions are taken through trade deals and trade sanctions rather than military actions. There will be interventions if a country starts an unjustified war.

We saw this in the form of trade sanctions for Russia when they annexed Crimea. (I would like to point out that I'm not saying this was or was not justified, I am merely stating what happened - just in case I want to visit Russia in the future)

We can see how these sanctions or embargos can devastate a country in the case of Cuba or North Korea. Although they might be less effective against large countries.