President Obama, exhausted on the campaign trial in 2008, told a crowd in Oregon about visiting “all 57 states.”

Everybody laughed, but the subject still comes up when someone wants to make a point that his civics knowledge might not be up to snuff.

There are 50 states, correct? No, technically there are 46. Virginia, Kentucky, Pennsylvania and Massachusetts have “commonwealth” in their official name, although there is no legal distinction.

Now let’s count …

We all know about the District of Columbia, which has the politically charged slogan “Taxation without representation” on its license plates. The District sends a delegate to the House of Representatives. Eleanor Holmes Norton calls herself “Congresswoman” on her website, an exaggeration. She doesn’t get a vote.

Don’t forget Puerto Rico, which recently defaulted on bond payments with a lot more grief ahead. It’s our own little Greece with winter league baseball.

Then add Guam (“Where America’s day begins”), the Northern Mariana Islands and the U.S. Virgin Islands.

American Samoa has been a territory since 1898.

Plus, we run the Palmyra Atoll in the Pacific, population zero. The U.S. Fish and Wildlife Service drops by occasionally to boss the birds around.

That adds up to … 57, if you define “state” loosely.

Civics class is dismissed.