RENO, Nev. - President Obama today argued that his foreign policy has ushered in a "new era of American leadership," while suggesting that Republican rival Mitt Romney has not shown he is ready to be commander in chief.

"Four years ago, I made you a promise. I pledged to take the fight to our enemies and renew our leadership in the world. As president, that's what I've done," Obama said at the national convention for the Veterans of Foreign Wars.

"As you reflect on recent years, as we look ahead to the challenges we face as a nation and the leadership that's required, you don't just have my words, you have my deeds. You have my track record. You have the promises I've made and the promises that I've kept," he said.

Just days after the campaigns suspended their attacks on one another following the Colorado massacre, the president returned to the previous combative tone of the race.

Without mentioning Romney by name, Obama pushed back against critics who have questioned his plans to wind down the wars in Iraq and Afghanistan.

"When you're commander in chief, you owe the troops a plan. You owe the country a plan. And that includes recognizing not just when to begin wars, but also how to end them," he said.

The Obama campaign today released a new video timed to the president's remarks praising his efforts to end the war in Iraq. The video came on what is now the deadliest day of the year in Iraq.

The president also took on Republicans in Congress, accusing them of "playing politics with our military."

Explaining it was "time to set the record straight," Obama said Republicans were willing to risk major defense cuts in order to preserve tax breaks for the wealthy.

"If the choice is between tax cuts that the wealthiest Americans don't need and funding our troops that they definitely need to keep our country strong, I will stand with our troops every single time," he said. "So let's stop playing politics with our military. Let's get serious and reduce our deficit and keep our military strong."

Automatic defense cuts are scheduled to kick in if Congress doesn't reach a deficit-reduction deal by the end of the year.

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"There's no reason that should happen, because people in Congress ought to be able to come together and agree on a plan, a balanced approach that reduces the deficit and keeps our military strong. It should be done," he said.

Obama, who met with survivors of the Aurora, Colo., movie theater massacre and the victims' families over the weekend, opened his remarks with a tribute to the service members who were killed.

"These young patriots were willing to serve in faraway lands, yet they were taken from us here at home. And yesterday I conveyed to their families a message on behalf of all Americans: We honor your loved ones. We salute their service. And as you summon the strength to carry on and keep bright their legacy, we stand with you as one united American family," he said.

Romney is scheduled to address the same audience Tuesday before departing for a foreign trip to England, Israel and Poland.