Here is Senator John Thune (R-SD), speaking on the floor of the United States Senate:

Ethanol producers have been ripping us off for a long time, and they’ve come to rely on that for a source of income. So it’s only fair to let them rip us off a little longer.

I’m quoting from memory, so I might have the wording slightly off, but that was the gist of it. Oh, wait, here’s the exact quote:

We have a lot of folks who made investments, you have people across the country whose livelihoods depend upon this. I think it makes sense, when we put policy in place and we say it is going to be in place for a certain period of time, that it be honored.

As you can see, my parapharase was accurate.

Senator Thune speaks in the great tradition of his institution. Back in 1848, senators by the score made exactly the same argument for preserving slavery. A lot of folks had invested in slaves, you know. And their livelihoods depended on it.

I wonder where Senator Thune will stand the next time there’s a bill to tighten up border security, or to speed up deportations of so-called “undocumented” workers. He could say something like:

We have a lot of folks who invested in finding jobs here, you have people across the country whose livelihoods depend upon being in this country…..

Of course the analogy is imperfect. Ethanol producers are socially destructive, converting valuable resources into fuel when they’d be more valuable as food. (If that weren’t the case, they wouldn’t need a subsidy.) Undocumented workers, by contrast, are socially constructive, performing tasks that people want to pay them for, without having to be subsidized to do it.

That’s why I’d be sympathetic to this argument in the case of immigration policy but find it laughable in the case of ethanol subsidies. If socially destructive behavior should be allowed to continue whenever someone’s invested in it, then we should just grit our teeth and tolerate everything from urban gangs to toxic waste dumps to corrupt politicians. I’m sure the latter will please Senator Thune.