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.
Russia's War Against Ukraine
Wall Street Journal: US scurries to shore up spying on Russia
Ukrainian army APC armoured vehicles move on a road to take up positions not far from the border between Ukraine and Russia, in the Kharkiv region of eastern Ukraine, on March 21, 2014. The EU welcomed Ukraine into the Western fold today, signing the political provisions of a landmark accord as a defiant Russia formally completed its takeover of Crimea. AFP PHOTO / SERGEY BOBOK
