Not sure about other countries, but I find it odd how allegiances with the U.S. tend to become Polar Opposites over time:
England: Bitter enemies in American Revolution and the War of 1812 but our closest ally since
Canada: Enemy in the War of 1812, ally since
Japan: Ally in WWI, Enemy in WWII, Ally since
Cuba: Ally in Spanish-American War, WWII, and Cuban Revolution. Enemy (negative relations) since
Philippines: Enemy in Philippine-American War, ally since
Iraq: Ally in Iran-Iraq War, enemy in Gulf War and Iraq war
Afghanistan: Ally in Soviet-Afghan War, Enemy in The War in Afghanistan
Russia: Ally in WWII, enemy for the Cold War, better relations now (but still shaky)