One general rule of modern politics is that the people who talk most about future generations — who go around solemnly declaring that we’re burdening our children with debt — are, in practice, the people most eager to sacrifice our future for short-term political gain. You can see that principle at work in the House Republican budget, which starts with dire warnings about the evils of deficits, then calls for tax cuts that would make the deficit even bigger, offset only by the claim to have a secret plan to make up for the revenue losses somehow or other.

And you can see it in the actions of Chris Christie, the governor of New Jersey, who talks loudly about acting responsibly but may actually be the least responsible governor the state has ever had.

Mr. Christie’s big move — the one that will define his record — was his unilateral decision back in 2010 to cancel work that was already under way on a new rail tunnel linking New Jersey with New York. At the time, Mr. Christie claimed that he was just being fiscally responsible, while critics said that he had canceled the project just so he could raid it for funds.

Now the independent Government Accountability Office has weighed in with a report on the controversy, and it confirms everything the critics were saying.