When Megan McArdle starts to make sense, you know you’ve entered Alice-in-Wonderland world.

She quotes today’s David Brooks’s column, calling it “the David Brooks equivalent of losing his temper,” which I must admit is pretty clever of her:

the Republican Party may no longer be a normal party. Over the past few years, it has been infected by a faction that is more of a psychological protest than a practical, governing alternative.

The members of this movement do not accept the logic of compromise, no matter how sweet the terms. If you ask them to raise taxes by an inch in order to cut government by a foot, they will say no. If you ask them to raise taxes by an inch to cut government by a yard, they will still say no.

The members of this movement do not accept the legitimacy of scholars and intellectual authorities. A thousand impartial experts may tell them that a default on the debt would have calamitous effects, far worse than raising tax revenues a bit. But the members of this movement refuse to believe it.

The members of this movement have no sense of moral decency. A nation makes a sacred pledge to pay the money back when it borrows money. But the members of this movement talk blandly of default and are willing to stain their nation’s honor.

Then she piles on to what Brooks said:

It would be bad enough if these people were simply against higher taxes, because then you might persuade them by pointing out that if we default, we’re probably going to end up with higher taxes, right now, in order to close the current gap between spending and tax revenue.

But when I point this out, the response in my comments and email and twitter is “Fine, I’ll accept higher taxes, as long as they come with radical changes in spending.” The BATNA (best alternative to negotiated agreement) is default on either our debt, or entitlements like Social Security that people have planned their lives around; the Democrats properly view this as a disaster. But I’m hearing from people who seem to think that it’s better than raising one thin new dime in taxes. This makes me very much afraid of where this is headed.

I’d feel good about this if I thought that the loonies in the Republican ranks read Brooks or McArdle and might have an “Aha” moment. I don’t. I think the Republican party has evolved into a group of maniacs who truly believe that the unelected Grover Norquist of “drown government in a bathtub” fame is their guiding light and his “no new taxes” pledge is the only guiding principle to which they must adhere.

I think this country is heading for a cliff and half the people ostensibly in charge are pushing it gleefully in that direction.