The suicide bombing at Moscow's busiest airport is a tragedy that "could have just as easily happened here," the commander of NORAD and the U.S. Northern Command said Tuesday.

"People think of us and the Russians as adversaries, and we're not, and particularly in this area," Adm. James Winnefeld said in an interview with The Associated Press. "We feel very badly for what happened to them in Moscow because that could have just as easily happened here."

Military-to-military relations between the U.S. and Russia are improving, Winnefeld said, and it's possible he will meet with Russian commanders in Russia if the two sides can work out the details.

"I would welcome the opportunity, candidly, and I would also welcome the opportunity to host a Russian counterpart here," he said.

Winnefeld said he has no direct counterpart in Russia but he is interested in meeting the commander of Russia's long-range aviation.

Winnefeld heads the North American Aerospace Defense Command, a joint U.S.-Canada command that is responsible for defending both nations from air attack and for monitoring potential maritime threats. He also leads the Northern Command, which is responsible for the military defense of U.S. soil and supporting civilian agencies in the event of a natural or human-caused disasters.

Both have headquarters at Peterson Air Force Base in Colorado Springs, Colo.

Winnefeld declined to say what impact the Moscow bombing might have on U.S security measures. That's a matter for the Department of Homeland Security and the Transportation Safety Administration, he said.

The explosion Monday at Domodedovo Airport killed 35 people and injured 180. No one has claimed responsibility, but Islamist separatist insurgents from Chechnya have taken credit for previous attacks in Moscow.

Winnefeld said regardless of why or where terrorists attack, they are relentless and fanatical and need only a single security weakness to stage a devastating strike.

"We call it shots on goal sometimes," Winnefeld said. "We have to be perfect goaltenders. All they have to do is get one shot through and they get to make an impact. And they certainly made an impact in Moscow yesterday. It was a real tragedy."