But I would not necessarily say that this is the choice the country faces. As I have argued from the outset, the American presidency is institutionally weak despite its enormous prestige. It is limited constitutionally, politically and ultimately by the actions of others. Had Japan not attacked the United States, it is unclear that Franklin Roosevelt would have had the freedom to do what he did. Had al Qaeda not attacked on 9/11, I suspect that George W. Bush's presidency would have been dramatically different.
The world shapes U.S. foreign policy. The more active the world, the fewer choices presidents have and the smaller those choices are. Obama has sought to create a space where the United States can disengage from active balancing. Doing so falls within his constitutional powers, and thus far has been politically possible, too. But whether the international system would allow him to continue along this path should he be re-elected is open to question. Jimmy Carter had a similar vision, but the Iranian Revolution and the Soviet invasion of Afghanistan wrecked it. George W. Bush saw his opposition to nation-building wrecked by 9/11, and had his presidency crushed under the weight of the main thing he wanted to avoid.
Presidents make history, but not on their own terms. They are constrained and harried on all sides by reality. In selecting a president, it is important to remember that candidates will say what they need to say to be elected, but even when they say what they mean, they will not necessarily be able to pursue their goals. The choice to do so simply isn't up to them. There are two fairly clear foreign policy outlooks in this election. The degree to which the winner matters, however, is unclear, though knowing the inclinations of presidential candidates regardless of their ability to pursue them has some value.
In the end, though, the U.S. presidency was designed to limit the president's ability to rule. He can at most guide, and frequently he cannot even do that. Putting the presidency in perspective allows us to keep our debates in perspective as well.
