It seems that Russia was able to evade U.S. surveillance techniques during its attacks on Ukraine.

But was it National Security Agency leaker Edward Snowden that allowed Russia to attack Ukraine without the U.S. knowing it was coming?

An article in Monday's Wall Street Journal about the failure of the U.S. to know what Russia was doing with Crimea and Ukraine didn't mention Snowden at all, but that didn't stop some in the intelligence community from making the link.

Rep. Mike Rogers, R-Mich., chairman of the House Intelligence Committee, told NBC “Meet the Press” host David Gregory on Sunday that Snowden was acting “very suspicious” during the event.

“We know today no counterintelligence official in the U.S. does not believe that Mr. Snowden, the NSA contractor, is not under the influence of Russian intelligence services,” Rogers said. “We believe he is. I certainly believe he is today. So now we all agree that he's under the influence of Russian intelligence services today.”

The WSJ notes that Russia may have changed its communication methods due to knowledge of U.S. surveillance techniques, which were highlighted by Snowden.

“Some U.S. military and intelligence officials say Russia's war planners might have used knowledge about the U.S.'s usual surveillance techniques to change communication methods about the looming invasion,” the WSJ said. “U.S. officials haven't determined how Russia hid its military plans from U.S. eavesdropping equipment that picks up digital and electronic communications.”

Snowden, who lives in Russia, has consistently denied he shared any secrets with Moscow. But U.S. intelligence officials and experts believe it's all but impossible for the former NSA employee to protect any information he might have with him from Russia's spies.

The WSJ article does offer a few theories that would have nothing to do with Snowden for why U.S. spies missed the Crimea operation.

"It isn't clear if Russian leaders deliberately avoided communicating about the invasion or simply found a way to do so without detection by the U.S,” the WSJ said. “Another possibility: Mr. Putin made a last-minute decision to seize Crimea—and told almost no one other than those responsible for carrying out the invasion. Some U.S. and U.K. officials believe that Russia's takeover plan was drawn up in advance and ready to go, reducing the need to discuss it."

Even so, the debate over his revelations is likely to heat up.