In this season of successive mass shootings, that erroneous conventional wisdom should not go unchallenged. Michael Wolkowitz, board chairman of the Brady Center to Prevent Gun Violence, calls the paralyzing myth of ’94 “the single biggest obstacle” to tightening the nation’s lax regulation of guns.

The notion that gun control was responsible for the Democrats’ debacle 15 years ago was floated by Richard Gephardt, the former Democratic House leader, and other pols and commentators after the ’94 election. But it was Bill Clinton who gave it current credence. “The N.R.A. could rightly claim to have made Gingrich the House speaker,” Mr. Clinton wrote in his 2004 autobiography, pumping up the gun lobby and, not incidentally, himself by attributing the body blow to his party to his principled leadership on guns.

It is hard to make a case that the assault weapons ban was decisive in 1994.

The law certainly enraged many N.R.A. members and might explain the loss of certain Democratic seats. However, there were other major factors in the Democrats’ 1994 loss, starting with perceived Democratic arrogance and corruption (overdrafts at the House bank came to symbolize that).

Add to that voter unhappiness with Mr. Clinton’s budget, his health care fiasco, the Republican Party’s success in recruiting appealing candidates, and that ingenious Republican vehicle for nationalizing the elections known as the “Contract With America.” The contract, by the way, did not mention guns.

Mr. Clinton’s successful 1996 re-election campaign actually stressed his gun control achievements. James and Sarah Brady spoke in prime time at the ’96 Democratic convention, and Clinton campaign ads trumpeted his role in enacting the assault weapons ban and the ’93 Brady law requiring background checks for gun buyers.