I endorse Barack Obama for a second term as US president, and therefore the most powerful man in the Western World.
My reason is that he has played this role very well, in my opinion. He has mostly used diplomacy and avoided the 'might is right' attitude of his predecessor George Bush. He has also shown the way forward on social matters, making progress on universal health care and LGBT inclusion.
It would be a shame for the US, and indeed the world, for him to be replaced by Romney, in my opinion.