Ahead of tonight's foreign policy debate, the Obama campaign is out with an ad that touts Obama's support for ending the wars in Iraq and Afghanistan -- and charges that a president Mitt Romney wouldn't have made the same call.

"A decade of war that cost us dearly," the narrator says. "And now for president, a clear choice: President Obama ended the Iraq War. Mitt Romney would have left 30,000 troops there and called bringing them home 'tragic.' Obama's brought 30,000 soldiers back from Afghanistan and has a responsible plan to end the war. Romney calls it Obama's 'biggest mistake.' " 

The ad rollout was accompanied by a memo from Obama's Romney debate stand in: Sen. John Kerry, who charges that Romney has offered "nothing but endless bluster and a record of dangerous blunders."

Obama has cast as successes the ending of the Iraq war and the wind down in Afghanistan, despite continued violence in both countries. Romney has been broadly critical of Obama’s withdrawal of troops from Iraq, and timetable for withdrawal from Afghanistan. He echoed Obama’s goal of withdrawing combat troops by the end of 2014, but said he’d let military commanders determine the pace.

Republicans have criticized Obama for failing to secure an agreement with Iraqi leaders to keep some peacekeeping forces in the country. Romney has charged that the troop withdrawals in Iraq and Afghanistan were "based upon electoral expediency, not military requirement," though polls have shown that most Americans support the moves.