"Our troops deserve better," he said. "This time, Democrats are determined to set a different course for the nation - now - to tell the truth to the American people and save the lives of American soldiers, and keep America safe.
"We want no more walls with 55,000 names of courageous Americans who were let down by their government," said Dean. "Democrats are united - we are united in our belief that we can and must win the war on terror."
The GOP advertisement featured a quote in which Dean said the Iraq war cannot be won by American forces. In his speech, he distinguished between Iraq and a broader terror war - saying 50,000 National Guard and reserve troops should be withdrawn within six months and that 20,000 others should be deployed to Afghanistan.
Dean also said American forces should "be stationed in the region, but not in Iraq" to deal with insurgents.
"I, as a Democrat, am proud of our troops," he said. "I am proud to lead a party offering America a new direction and together, America can do better."