Forty years ago Tuesday, the U.S. Supreme Court decided one of its most important cases: Doe v. Bolton.

Never heard of it? Not surprising, but sad. That decision set the divisive tone of American political debate for the 20th century's last quarter and probably far into this one. Upon it has rested the fate of millions, in their quality of life and in their very existence. Its impact is many times more consequential than the current uproar over gun rights.