Special Report: How the U.S. made its Putin problem worse

1 OF 9. U.S. President Barack Obama (L) meets with Russian President Vladimir Putin during the G8 Summit at Lough Erne in Enniskillen, Northern Ireland, in this June 17, 2013 file photo.

CREDIT: REUTERS/KEVIN LAMARQUE/FILES

(Reuters) - In September 2001, as the U.S. reeled from the terrorist attacks on the World Trade Center and the Pentagon, Vladimir Putin supported Washington's imminent invasion of Afghanistan in ways that would have been inconceivable during the Cold War.

He agreed that U.S. planes carrying humanitarian aid could fly through Russian air space. He said the U.S. military could use airbases in former Soviet republics in Central Asia. And he ordered his generals to brief their U.S. counterparts on their own ill-fated 1980s occupation of Afghanistan.

During Putin's visit to President George W. Bush's Texas ranch two months later, the U.S. leader, speaking at a local high school, declared his Russian counterpart "a new style of leader, a reformer…, a man who's going to make a huge difference in making the world more peaceful, by working closely with the United States."

For a moment, it seemed, the distrust and antipathy of the Cold War were fading.

Then, just weeks later, Bush announced that the United States was withdrawing from the Anti-Ballistic Missile Treaty, so that it could build a system in Eastern Europe to protect NATO allies and U.S. bases from Iranian missile attack. In a nationally televised address, Putin warned that the move would undermine arms control and nonproliferation efforts.

"This step has not come as a surprise to us," Putin said. "But we believe this decision to be mistaken."