There's a problem with American companies moving overseas, says Fortune Editor-at-Large Allan Sloan. When companies avoid taxes, they're leaving Americans to pay the bill, he said.

It's perfectly legal for a company to leave the country, he wrote in a recent article, but it threatens to undermine America's tax base.

A company does this by reincorporating in a place like Ireland, where the corporate tax rate is 12.5%, compared with 35% in the U.S. Inversion also makes it easier to divert what would normally be U.S. earnings to foreign, lower-tax locales. But being legal isn't the same as being right. If a few companies invert, it's irritating but no big deal for our society. But mass inversion is a whole other thing, and that's where we're heading.

If companies can legally dodge corporate taxes in the U.S., is there any reason they should not? Should Congress put a stop to this, but risk losing some American companies to other countries? Leave your thoughts below.