US races to close spying gaps after Russia's Crimea moves elude them

March 23, 2014: Activists stand guard during a pro Russian rally at a central square in Donetsk, eastern Ukraine. About 5,000 people demonstrated in Donetsk in favor of holding a referendum on secession and absorption into Russia similar to Crimea's. A statue of Lenin is seen in the background. (AP Photo/Sergei Grits)

U.S. military satellites spied Russian troops amassing within striking distance of Crimea last month. But intelligence analysts were surprised because they hadn't intercepted any telltale communications where Russian leaders, military commanders or soldiers discussed plans to invade.

America's vaunted global surveillance is a vital tool for U.S. intelligence services, especially as an early-warning system and as a way to corroborate other evidence. In Crimea, though, U.S. intelligence officials are concluding that Russian planners might have gotten a jump on the West by evading U.S. eavesdropping.

"Even though there was a warning, we didn't have the information to be able to say exactly what was going to happen," a senior U.S. official says.

To close the information gap, U.S. spy agencies and the military are rushing to expand satellite coverage and communications-interception efforts across Russia, Ukraine and the Baltic states. U.S. officials hope the "surge" in assets and analysts will improve tracking of the Russian military and tip off the U.S. to any possible intentions of Russian President Vladimir Putin before he acts on them.

The U.S. moves will happen quickly. "We have gone into crisis-response mode," a senior official says.

Still, as Russia brings additional forces to areas near the border with eastern Ukraine, America's spy chiefs are worried that Russian leaders might be able to cloak their next move by shielding more communications from the U.S., according to officials familiar with the matter. "That is the question we're all asking ourselves," one top U.S. official says.

The Obama administration is "very nervous," says a person close to the discussions. "This is uncharted territory."

It all comes amid the backdrop of a worried government in Kiev. Ukraine's foreign minister said Sunday that the troop buildup is increasing the possibility of war with Russia.

Months before the takeover, U.S. spy agencies told White House policy makers that Mr. Putin could make a play for Crimea, home to strategically important Russian naval installations. That led to an unsuccessful diplomatic push by the Obama administration.

When the moment arrived, U.S. attention was focused on the troops on Russian soil. Instead, forces already inside Crimea were spearheading the takeover of the peninsula, before U.S. spy agencies fully realized what was happening.

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