Romney has fiercely criticized the Obama administration for not being forceful enough on the world stage and too often "leading from behind." Obama has put more emphasis on coalitions when exerting power across the globe.
A New York Times report that the Obama administration may negotiate with Iran about its nuclear program after the election may give Romney another opening to cast the president as too accommodating.
This is a war-weary country, however, and Obama has already implied that a Romney administration would mean returning to the policies of President Bush, both on the domestic front and internationally.
"If Gov. Romney is suggesting that we should start another war, he should say so," the president told 60 Minutes last month when asked about Romneys charges that Obama was not aggressive enough with Iran.
Nor can Obama entirely distance himself from the Bush policies he has long criticized. He has yet to fulfill his promise to close the prison at Guantanamo Bay, Cuba, for instance.
5 Second-term agenda. Obama has repeatedly criticized Romney for failing to explain how his tax and budget policies add up, and what expenses and tax deductions they would support.
Nor has Romney offered many specifics for where he actually differs with Obama on the stickiest foreign policy issues, such as Iran, Afghanistan and Israel.
But Obama likewise has yet to offer a real explanation for what his second term would look like, beyond broad platitudes.
The presidents campaign has concentrated for months on making Romney an unacceptable alternative to the president, but with two weeks to go he and Romney are essentially tied. Tonight will be his last, best opportunity to explain his plans for the next four years.