I don't think that Liberals "hate America". But I do think that some Liberals have forgotten what make this country strong to begin with. They have forgotten that what made us one of the richest nations in the world is the ideal that if you're smart and/or work hard you can make a good living for yourself, but if you're stupid and/or lazy that you'll be poor. They have forgotten that the only reason we can care about the social issues they're so concerned about; helping the poor, the environment, education, ect... is because the smart and hard working people of this country have created enough wealth that we can afford to spend money on these problems.
I think it could also be argued that many ultra conservitives "hate America" because our freedoms mean that were free to do things that they consider immoral.