erm  one of the best known commentators on the american president, a man called richard newstat er  who's occasionally known as mr williams because he's married to er shirley williams a  clapped-out social democratic politician of er yesteryear, erm  richard newstat once said, well once said many things but er on this particular occasion said that er if you want to know what presidential power is, it is simply the power to persuade  and that er when you look for er an american president what you need to look for er is not somebody who is clear minded, far sighted and so on but you need somebody who has the capacity  the skill, the talent, to persuade other people to do what he wants them to do.