He should pay attention for what is going on in the world outside the US. He should close Guantanamo and renounce torture defintely, once and for all, and he should apologize for all the injustices that have been done. He should end the endless interference of the US in other people's businesses, make an end to imperialism He should clean up the mess in Iraq and leave, closing all fortresses built there. He should care for his own people, e.g. giving them health care that deserves the name.
Senator Gravel's National Initiative for Democracy would be a great start, along with a comprehensive Universal Healthcare plan, withdrawal from imperialist campaigns in the Middle East, and a huge degree of investment in renewable energy sources.
