This week's heartening rapprochement of the U.S. and Cuba reminds us of the complexity of regional security relations and the very long shadow of the Cold War. Washington, Moscow, and Berlin would do well to build on the spirit of this week's breakthrough in the Western Hemisphere to find a similar solution in Ukraine. It is time to end the Cold War once and for all.

Former President of the Soviet Union Mikhail Gorbachev last November.

In all entanglements, each side tends to see the other as the sole aggressor. This is not mere cynical posturing. It is probably hardwired into our imperfect cognitive apparatus. Jesus was remarking on this bias when he cautioned his followers against pointing to the mote in the other's eye while neglecting the beam in their own. Cuba and Ukraine are classic cases in point.