Oil from any source is dirty, environmentalists apparently forget who we buy a majority of oil from, OPEC and Venezuela. Why not buy it from an ally? It’s worse for the environment by how it’s produced but much less risky in terms of transit. Once again you’ve not explained how american environmentalists will block a pipeline but not giant floating disasters like the Valdez, or the Gulf spill. Again I point to the fact that this is visable, unsightly, the oil rigs and ships are far from sight, so the fickle forget.