Obama and Medvedev: a new START (11 images)

U.S. President Barack Obama (L) and Russian President Dmitry Medvedev speak after signing the new Strategic Arms Reduction Treaty (START) at the Prague Castle in Prague on April 8, 2010. UPI Photo/Alex Natin.

U.S. President Barack Obama speaks after signing the new Strategic Arms Reduction Treaty (START) at the Prague Castle in Prague on April 8, 2010. UPI Photo/Alex Natin.

U.S. President Barack Obama speaks after signing the new Strategic Arms Reduction Treaty (START) at the Prague Castle in Prague on April 8, 2010. UPI Photo/Alex Natin.

U.S. President Barack Obama speaks after signing the new Strategic Arms Reduction Treaty (START) at the Prague Castle in Prague on April 8, 2010. UPI Photo/Alex Natin.

U.S. President Barack Obama (L) and Russian President Dmitry Medvedev speak after a signing ceremony of the new Strategic Arms Reduction Treaty (START) at the Prague Castle in Prague on April 8, 2010. UPI Photo/Alex Natin.

U.S. President Barack Obama (L) and Russian President Dmitry Medvedev hold the singed new Strategic Arms Reduction Treaty (START) at the Prague Castle in Prague on April 8, 2010. UPI Photo/Alex Natin.