Why Can't Friedman Say What's So Obvious?

Friedman is once again beating the drums for a gasoline tax.

His next to the last paragraph:

That's why we need an urgent national effort, starting with a gasoline tax, to move the U.S. economy onto a path of more fuel-efficient cars and renewable energy. If we do it, everyone will follow.

No, Thomas, we can't have a high gasoline tax. Low income people do not have alternatives to using cars. With some exceptions, public transportation does not exist in the United States. The U.S. is different from Europe.

What we need is a high tax on gas guzzling cars and on big homes that waste huge amounts of energy on heating in the winter and cooling in the summer.

Why can't Friedman say that? What's stopping him?