FRIDAY NEWS: * The tough sell: on America's responsibility in the new Middle East . * By the numbers: 'growth in college tuition vs. growth in earnings for college graduates.' * Andrew Cohen on hypocrisy at the Supreme Court . * The conspiracy of cartography . * Whoah. How about a actual picture of the DNA double helix ? * Messenger identifies water on Mercury . * No one was shot or stabbed for one whole day in New York City . * Ten television cliffhangers that could have worked as series finales .