Last week House Republicans voted for the 40th time to repeal Obamacare. Like the previous 39 votes, this action will have no effect whatsoever. But it was a stand-in for what Republicans really want to do: repeal reality, and the laws of arithmetic in particular. The sad truth is that the modern G.O.P. is lost in fantasy, unable to participate in actual governing.

Just to be clear, I’m not talking about policy substance. I may believe that Republicans have their priorities all wrong, but that’s not the issue here. Instead, I’m talking about their apparent inability to accept very basic reality constraints, like the fact that you can’t cut overall spending without cutting spending on particular programs, or the fact that voting to repeal legislation doesn’t change the law when the other party controls the Senate and the White House.

Am I exaggerating? Consider what went down in Congress last week.

First, House leaders had to cancel planned voting on a transportation bill, because not enough representatives were willing to vote for the bill’s steep spending cuts. Now, just a few months ago House Republicans approved an extreme austerity budget, mandating severe overall cuts in federal spending — and each specific bill will have to involve large cuts in order to meet that target. But it turned out that a significant number of representatives, while willing to vote for huge spending cuts as long as there weren’t any specifics, balked at the details. Don’t cut you, don’t cut me, cut that fellow behind the tree.

Then House leaders announced plans to hold a vote on doubling the amount of cuts from the food stamp program — a demand that is likely to sink the already struggling effort to agree with the Senate on a farm bill.