Barack Obama takes over as US President with a promise to dramatically change America and make it a fairer place. He is inheriting the worst economic crisis in almost a century, and a country so unequal that 23,000 people die every year because they cannot afford basic healthcare. To close the gap between rich and poor Obama will have to take on the might of the corporate world, which wields enormous influence in Washington. Can he change the world's most powerful country - and should he?