[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2008/images/09/27/art.ap.debate1.jpg caption="Sens. McCain and Obama went head to head Friday night in their first presidential debate."]
WASHINGTON (CNN) - In their first head-to-head debate, Sen. John McCain criticized Sen. Barack Obama as a candidate who "doesn't understand" the key issues the country faces, and Obama linked McCain to President Bush on several issues.
"I'm afraid Sen. Obama doesn't understand the difference between a tactic and a strategy," McCain said Friday as the two traded jabs over Iraq.
Obama shot back, "I absolutely understand the difference between tactics and strategy. And the strategic question that the president has to ask is not whether or not we are employing a particular approach in the country once we have made the decision to be there."
McCain drew from his experience overseas as he tried to portray himself as the more qualified candidate.
"Incredibly, incredibly Sen. Obama didn't go to Iraq for 900 days and never asked for a meeting with Gen. [David] Petraeus," he said.
McCain slammed Obama for not supporting the surge, an increase of about 30,000 troops to Iraq in early 2007. Bush sent the additional troops as part of a campaign to pacify Baghdad and its surrounding provinces.
"John, you like to pretend like the war started in 2007," Obama shot back. "You talk about the surge. The war started in 2003, and at the time when the war started, you said it was going to be quick and easy. You said we knew where the weapons of mass destruction were. You were wrong."