First, it's my understanding rights for pipeline land are already secured
Second, Republitarians are not opposed to the righteous use of eminent domain. When in the broad interest of the vast majority (not majoritarianism, where the slight majority pushes around a minority), eminent domain is fine. The government must pay fair market value and I would argue to err on the high-side, since the big, powerful government is pushing the little guy around. Highways, bridges, pipelines and canals are all in the public interest (Wall Mart's are not). Especially when publicly debated and every attempt is made to accommodate owners. For example, if a landowner doesn't want to sell and it's a minor inconvenience for the government to go around, they should go around. This is especially true for pipelines across vast stretches of empty farmland.
Too often eminent domain is used to push the little guy around. That doesn't seem to be the case here. Objections are out of the State Department, not landowners. If environmentalists truly want a valid objection, they should buy blocking land and demonstrate more than a mosquito sanctuary. Use the land to build something of productive value. As it is, they have no (moral) standing as far as I can see.
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