Transcript for Security implications follow Russia subway attack

Let's talk about that more now with terrorism expert Miker Leiter and to pick up on what Alex was saying this area, Kyrgyzstan, the caucuses, a hot bed of jihazists, unrest for a generation for Putin. It really has. Both the caucuses which are 2,000 miles to the west but also further to the east in Kyrgyzstan and thousands of fighters not only from Russia but Kyrgyzstan and Uzbekistan go earlier to Pakistan and more recently to Syria. We've seen in the past that Putin has cracked down in chechnya, in those republics, some concern now that Putin and his government may use this as an opportunity to crack down on these broader protests they've been facing. I think it's fair to say Putin never faces this sort of adversary with a gentle glove. He hits this with a hammer and I think it's very possible that he will expand that. He will go after the caucuses. He will go after being harder fight in Syria and I think he could use it as an excuse for any suppression he wants. That's the fight in Russia but there is generalized concern across Europe particularly threats against public transportation and subways. That's right. We had the bombing in Brussels in 2016. We had threats in New York subway in 2009. These are really susceptible targets. Lots of people in close space and screening to get on is easier than something like an airplane in the U.S. Or ov overseas. Even though there's no claim of responsibility this idea that there was a second bomb perhaps in a fire extinguisher could have been far worse. It could have been far worse and officials overseas and in the U.S. Will learn from that and look at how it was hidden. How the train operator responded. It doesn't matter where it is, anyone could face it. You have to understand how can you win this cat and mouse game of terrorism offs trying to defend against these sorts of innovative threats. We do know the train operator by continuing to go on continued to save lives. Wouho knows. If it was a fire on board it could have accelerated it. Trying to find it before it happens whether in fire extinguishers or laptops on planes.

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