WASHINGTON -- President Barack Obama's former national security adviser says rejecting the Keystone XL pipeline would be a gift to Vladimir Putin.

James Jones is testifying today at a Senate hearing on whether approving the pipeline is in the U.S. national interest.

He says energy scarcity is a powerful geopolitical weapon -- as evidenced now in Ukraine, and at various times in Iran and Venezuela.

Naming the Russian leader personally, he says the world's bullies are watching the KXL debate, and hoping to see a weaker U.S. that foregoes opportunities for energy independence.

He says he can't understand why the U.S. would spend billions and risk soldiers' lives to stabilize oil sources abroad -- then reject a piece of vital infrastructure at home.

He says climate change requires action, but can't see how the Keystone pipeline determines that issue.

The hearing is being held while the Obama administration determines whether the Alberta-to-Texas pipeline is in the U.S. national interest. A decision is expected within months.