Robert Dallek — American Historian born on May 16, 1934,

Robert Dallek is an American historian specializing in the Presidents of the United States. He retired as a history professor at Boston University in 2004 and previously taught at Columbia University, the University of California, Los Angeles, and Oxford University. As of November 2013 he teaches at Stanford University's Stanford in Washington program in Washington, D.C. He won the Bancroft Prize for his 1979 book Franklin D. Roosevelt and American Foreign Policy, 1932–1945 as well as other awards for scholarship and teaching... (wikipedia)

Don't be intimidated by people who seem to be experts. Hear their points of view and get their judgements. But at the end of day, you've got to make a judgement because it's not their life that's going to be affected so much as your future.
Despite all the public hand-wringing about negative advertising, political veterans will tell you that it persists because, more often than not, it works. But tearing down the other guy has another attraction: It can be a substitute for building much of a case for what the mudslinger will do once in office.
The Cold War is over. The kind of authority that the presidents asserted during the Cold War has now been diminished.
Whatever the long-term legal prospects for same-sex marriage, President Obama's willingness to put the matter front and center in an election year can at least make him a candidate for inclusion in Kennedy's Profiles in Courage.
Clinton's egregious act of self-indulgence was outdone by an impeachment based not on constitutionally required high crimes and misdemeanors but on a vindictive determination to bring down a president who had offended self-righteous moralists eager to put a different political agenda in place.