By JENNIFER LOVEN 2010-07-10T07:09:27Z WASHINGTON (AP) -- With the conclusion of the biggest spy swap since the Cold War, the U.S. has defused a thorny diplomatic problem quickly and cleanly - and avoided damaging recent efforts to improve relations with Russia. And Moscow has escaped further embarrassment over a group of spies that over the years apparently had little if any success in ferreting out any useful secrets....