Oil may be fungible, but it is undeniable that a large percentage of it comes from oppressive or outwardly hostile regimes. There's no reason why we should have to coddle governments such as Saudi Arabia, or Iran should be awash in money to help fund terrorist groups and its nuclear program, or Chavez should have the financial ability to assert himself in South America. If we were to develop alternative fuels, we could also export those technologies and make other nations less dependent. Look at how much China's oil interests in Sudan have prevented us from being able to take more aggressive steps to end the ongoing genocide in Darfur, to cite one example.
I'm not saying that I don't have issues with government involvement in energy. I do, however, have a problem when conservatives are dismissive of any attempt to argue that our dependence on foreign oil is a problem.