Vietnam War-weary voters are experiencing another battle in the presidential election concerning what the two contenders did or failed to do more than 30 years ago. President Bush’s Air National Guard record is at issue this time, giving Republicans another chance to be infuriated, but they should make no mistake. The intense scrutiny of Mr. Bush’s record was caused by the scrutiny of Mr. Kerry’s record by the Swift Boat Veterans for Truth. This latest fight was begun by friendly fire.

Most Americans may not vote based on how the two candidates spent their time in the military. They both served a long time ago in a difficult period of the nation’s history, and there have been many more measures since to gauge their fitness for the White House. It isn’t that their military records should be ignored, but they ought to be placed in the context of their lives.

In the case of the president’s guard service, he has never claimed any great achievement there. The stories this week revolve around new allegations reported by The Associated Press and others that the president did not fulfill his duty after he was given approval to transfer from Texas to Alabama in 1972, that he received unauthorized payments and that the general in charge of the Texas Air National Guard, a friend of the Bush family, pressured Lt. Bush’s immediate superior to “sugar coat” his evaluation.

Politically, it had been risky for Sen. Kerry to make an issue out of the president’s guard service. To do so would look like a cheap shot at men and women who served in the guard. Beyond the material that had surfaced during Mr. Bush’s gubernatorial and first presidential races, the senator and various Democratic groups were careful with the president’s record and instead focused, obsessively at times, on the senator’s own record. That changed with the attacks by the Swift Boat Veterans for Truth, which allowed Sen. Kerry to act simultaneously as the victim of an attack and as an aggressor.

The charges against the president are serious, of course, but they are also about events that occurred 32 years ago. They might never have come up had the Bush campaign squashed the kinds of attacks against Sen. Kerry that had been also launched against Sen. John McCain in 2000 and former Sen. Max Cleland in 2002. This time they have put the president on the spot, though rather than lead to a truce they are more likely to provoke another round of strike and counter-strike.