I would apologize to the world, saying "Yes, we as a nation did some really dumb shit in the past, backed some people who turned out to be dictators, murderers, and were generally bad for all nations, especially their own. We're sorry. We now know we shouldn't have done that. We won't do it again. Well, I cannot speak for those who will follow my term, but I will not do that, and I will take whatever steps are available to me by our Constitution to ensure that foolish errors like those we have committed in the past cannot and will not happen again."
I would say to the people of the world, "America is a nation who is divided from within. We have seen that the way the partisan system functions in this country does not work, and we as a nation cannot make up our minds about anything. I am sorry for that too. We are quite frequently a nation of idiots governed by idiots. Our citizens are uninformed about a great many important issues. We are not the perfect nation we like to imagine we are. We may have done things that have served to alienate us from you. For that I am sorry. We have thrown our weight around, done what we wanted, and looked after our own best interests above all else. We have disregarded the United Nations. We have committed acts that we ourselves would call "terrorism," if we had the courage and honesty to question them. For that I am sorry. I give you my pledge now that for the next four years, and God willing much much longer, we will act in a manner that is not only fitting of the nation that our founding fathers wished for us to be, but in a manner that embraces what is in the best interest of all mankind, not merely those within our borders.
"We have become too proud of too little, we have scorned those who sought to aid us. We have hurt those who have done no harm to us. We have sought to control those nations we felt threatened by. We have made mistakes. I say now, I regret, I am ashamed of those mistakes. I ask the international community to forgive us. Not to forget those mistakes have been committed, but to understand that today we will finally own up to them."
I would nullify the USA PATRIOT Act, and end the growing spectre of a police state.
I would re-establish our relationship with NATO, the UN, and seek to regain the trust of our former allies.
I would chastise those who seek to amplify the unnecessary and foolish emnity between the parties of the government, reminding them that they serve at the pleasure and with the trust of the voting public.
I would urge every citizen of the United States to remember that THEY are the ones who elect us, and should not live in fear or anger of their elected officials. I would ask that they take the time to understand the issues that face them, to understand both how the issues will affect both them and everyone.
I would act in a matter befitting the office of the President, and not use it to advance my own portfolio.
I would expose the ultra-fundamentalist, neo-conservatives for the American Taliban that they are.
I would (belatedly) affix my name and my country to the Kyoto Accord and rejoin the Non-Proliferation Treaty.
I would remember that the world will continue after my Presidency, and see to it that the next person to take office has a safer, cleaner, more peaceful country and world to look out over, and attempt to improve even further, for the good of all mankind.