Obama compared to JFK:
A torch is passed to the first President from his generation and the first from a large ethnic group, who is notable for lofty rhetoric, boundless optimism, an ability to inspire, and a tendency to make really damn good speeches, who selects as his running mate a long-tenured Senator from the older generation. The parallel, one really friggin' hopes, stops there.
It does, and here's why.
Obama isn't threatening the status quo like Kennedy did. Kennedy sought to unilaterally dismantle the CIA and drastically reverse our Cold War policies toward the Soviets (and by extension our whole nuclear policy.) Kennedy's own military commanders and CIA officials ran black ops for the express purpose of embarrassing Kennedy and forcing him to act aggressively against the Soviets. Kennedy was in direct opposition, sometimes publicly but often privately, to the powers that be. He was secretly in talks with both Kruschev and Castro while his military was advising him to nuke and/or invade Cuba, assassinate Castro and tell the USSR to eat a dick. At one point Kennedy was ordering the arrest and detention of Cuban guerrillas trained by the CIA and ordered to attack Cuba, because the CIA went ahead and told them to commence their operations even though Kennedy directly order the CIA and the military not to do it.
That's the degree to which Kennedy threatened the establishment that has the power to kill.
Obama? He's in with Wall Street, he's on their side as his cabinet appointments make clear. The military has his back, who Obama just re-slathered in hero sauce by getting Bin Laden. Our military has been fighting a "hot war" against terrorism for close to a decade and I think they're pretty damn tired of fighting and dying for essentially nothing. We don't think we can win in Afghanistan, honestly, compared to the anti-communists who thought we could beat the USSR. Obama's goals and the military's goals most align on this, I think.
The hits the establishment is going to take are out in the public, in the media, voted on and essentially authorized by the American people. For all his new dawn, new day talk, Obama has turned out to play
very well with the political establishment. He's not Kennedy because he's not willing to take direct action in the face of entrenched opposition. Guantanamo? The half-in, half-out thing in Libya? His cabinet appointments? The debt ceiling debate? All of these point, to me, to a president who isn't willing to challenge the status quo and therefore isn't in danger of being snuffed out. Kennedy fired the director of the CIA under him after the whole Bay of Pigs incident (which I won't go into.) That's a powerful, independent executive. Obama is nothing like that.
About the only other direct comparison between the two you can draw is how much the media adore them.