Former U.S. Secretary of Defense Robert Gates told "One Nation with Brian Kilmeade" on Saturday what Russian President Vladimir Putin would need to achieve to secure Ukraine and install a puppet government.

ROBERT GATES: He has nowhere near enough troops to put down a rebellion among millions of people in Ukraine, so he's going to have to keep a significant military force in Ukraine. He's probably going to have to increase it if he wants to hold on to that country, even if he imposes a puppet government, he's going to have to keep forces there to keep that government in power. So I think between having his hands full in Ukraine and the risk of a true war with NATO, I think he'll be very cautious about doing anything that crosses borders of NATO countries.

Now I do think in the Baltic States, there is the chance that he will use intelligence means — cyber, covert operations and so on — to try and create unrest in those countries. Thirty percent of the population in Estonia and Latvia, both are Russians. And so I can see him trying to create problems in the Baltic countries, but I don't see him invading, and I would just make one final point. I think that what's really important here are the troops that the United States has sent, and it's not just the 101st Airborne and the 82nd Airborne, it's sending heavy armored brigades. This is serious stuff, and that's what's needed to send a signal to the Russians that crossing into a NATO country, we mean business. And I think sending even more of those armored brigades would be a good idea.

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