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A congressional hearing yesterday in Washington, D.C. focused on global cyber threat and almost all of it centered on Russia, which the Obama administration accuses of hacking into American computer systems and interfering in last year's U.S. Election.

A Republican senator said, quote, "Every American should be alarmed by Russia's attacks on our nation." A Russian spokesman said his country was sick and tired of people, quote, "irresponsibly blaming everything on Russia."

Taking a look at Russian President Vladimir Putin — what makes him tick?

PHIL BLACK, CNN INTERNATIONAL CORRESPONDENT: Some have believed Vladimir Putin could be the most powerful man in the world. Not everyone sees him that way. But Putin has powerful levers, he's often willing to use — including cyber power, military might and a cult of personality. Together, they form an often effective web of influence.

While Moscow denies highly skilled hackers tried to influence the U.S. election, they've also been accused of spying and causing big disruptions in other countries, like Estonia and Ukraine — claims Russia also rejects. Russia's enormous hacking power, state and criminal, isn't a new. It traces back to the USSR when its universities were designed to produce world class engineers.

Putin's power is also hugely enhanced by his very personal control of Russia's vast military, much of it including the nukes, is also a Soviet legacy. So, Putin is pumping extraordinary amounts of money to modernization, but most analyst agree Russia's conventional forces are still only mighty enough to project power close to its borders.

Russia also used limited air power to successful prop up the Syrian regime. But critics say that works because of Putin's willingness to indiscriminately bombard civilian areas, something Moscow denies.

One of the biggest sources of Putin's power is his own extraordinary popularity at home. The more other world leaders criticized him, the more Russians celebrate their president. His approval figure soared with Ukraine and spiked again with Syria.

The reason: many Russians really care about their country's ability to influence world events, even if it comes to sanctions and a hit to their own quality of life. They're proud of it. Putin also benefits from a political system and the media landscape with zero tolerance for criticism.

So, no doubt, Vladimir Putin is powerful and unpredictable, but he's also limited by some pretty big problems. The Russian economy isn't going anywhere. That's why there is another popular theory about Putin and his web of influence, as someone who plays a weak hand very well.