A lot of people wonder what the negativity toward America that comes from the left is derived from. People remember Chomsky's infamous apologia for Pol Pot and the Khmer Rouge after the Vietnam war, people hear Zinn's endless tirades about America's "genocidal imperialism," people hear the anti-American pronouncements coming from the San Francisco Board of Supervisors, people remember Ramsey Clark and Lynn Stewart defending America's worst enemies, people remember Sean Penn and Jane Fonda giving aid and comfort to our enemies during times of war and of course all the treachery coming from the left during the Cold War, and they wonder - what does the left have against this country?
Obviously, the major point of contention between right and left stems from the classic argument between more continental European collectivist (Hegelian) values and the more British/American values of individualism, liberty and personal responsibility.
But taking that realization a step further - by putting it in the context of history - you begin to be able to see things from the left's perspective.
Looking around today, what you find is British/American modes of economy and governance dominating the world. More and more developing countries are opening up their economies to foreign investment and competition and it's no longer a question whether free markets and democracy have truly triumphed over collective authoritarian models - people are just doing it.
The world is following America's example, and America does and has always represented the height of individualist, liberal (in the classic sense) way of life, and it is why America has the most powerful economy in the world.
America reminds the left, each and every day, of the triumph of individual liberty over collective authority.