While Russia invades Ukraine and steps up its bombing of cities, former Connecticut Sen. Joe Lieberman told "The Brian Kilmeade Show" that the United States cannot stand by and do nothing. The 2000 Democrat VP nominee said Thursday the U.S. and NATO can take further actions to help Ukrainian forces.

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JOE LIEBERMAN: And the question is now really one for Putin is he just bombarding the Ukrainian cities to get to a point where there can be a cease-fire on terms that are acceptable or advantageous for him? Or does he really mean to demolish Ukraine the way he did Chechnya? And the challenge for us now? And by us, I mean, the U.S. and NATO, are we going to stand back? I know. And let a kind of almost you might say genocide. It's the murder of the Ukrainian people just because they are Ukrainians. He's targeting civilians. And my answer to that is, I hope not. I know they're not willing to do a no-fly zone, but there is a lot more they can do on the ground with more sophisticated weapons. Look, we could also covertly send in special forces to aid the Ukrainians and the NATO. Allies in Europe have tremendous capabilities along those same lines. I think morally, we just can't stand back and watch this.

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