TO REVIEW the doleful history of our dealings with Saddam Hussein may be futile in view of what is happening. But it is a useful reminder of an eternal truth: If you don't do the decent thing, you can end up doing the ultimate thing, which in this case is going to war in the Persian Gulf with a maniac armed with poison gas.

Poor April Glaspie, our erstwhile ambassador to Iraq, has taken the rap for all but inviting Saddam into Kuwait. In an interview she had with him a week before the invasion, she said, on instructions from the State Department, "we have no opinion on . . . your border disagreement with Kuwait." But that was merely the last straw in a seven-year Republican policy of not just appeasing Saddam but coddling him.

Whenever we do something repulsive, like ignoring Saddam's use of poison gas against the Iranians and his own Kurds, it is for some geostrategic reason or in behalf of some special interest. With Saddam, both circumstances obtained. Because of our bitter antipathy towards Iran over the humiliating hostage episode, we took Iraq's side in the eight-year war between the two scorpions. And when it came to imposing sanctions for Saddam's murder of thousands of people, we backed off because the oil companies, the farm lobby and assorted others who benefited from the stroking of the thug didn't want him upset.

For a definitive answer on why we treated him so tenderly, we should perhaps apply to the chairman of the Joint Chiefs of Staff, Colin Powell -- Ronald Reagan's national security adviser during the war's latter years -- or to George Bush -- Reagan's vice president and co-pilot.

The administration issued some 15 statements on the matter. When Vice President Bush spoke against the use of poison gas, he did not mention Iraq or Saddam.

It isn't as if the Reagan-Bush administration didn't know what was going on. Although Reagan's first secretary of state, Alexander Haig, spent considerable money and rhetoric trying to pin a poison-gas label on the Soviets in Afghanistan (the substance turned out to be bee-excrement), Saddam's poison gas-attacks on the Iranians from 1983 through 1987 were documented by eight different United Nations investigative teams.

In 1988, Sen. Claiborne Pell (D-R.I.) sent Peter Galbraith, a member of the Senate Foreign Relations Committee staff, to Iraq to investigate charges of widespread use of poison gas on the Kurds. He found that as many as 20,000 Kurds had been gassed to death and that villages that had existed since the beginning of civilization had been extinguished. Even so, the Reagan administration continued to subsidize the author of these atrocities. Saddam received loans and farm credits to the point where Iraq was just behind Israel and Egypt as our largest recipient of foreign assistance.

The new chairman of the Republican Party, Clayton Yeutter, in his maiden speech, issued an ugly warning to Democrats in Congress who voted in favor of sanctions instead of war. He said they would pay. Why should they pay any more than the Republicans who turned the other cheek for seven years of subsidy and appeasement?

Only the Senate looks good in this sad history. After one day's consideration, it voted on Sept. 9, 1988, for Pell's "Prevention of Genocide Act," which would have imposed strict sanctions against Iraq. The sanctions were watered down in the House and died in conference at the behest of the administration, which called them "premature."

Last April, GOP Senate Whip Alan Simpson told Saddam soothingly that his problems were "with the Western media and not with the U.S. government." According to a transcript furnished by the Iraqis and not disputed in Washington, Simpson characterized the press as "haughty and pampered" -- epithets much better applied to Saddam.

As late as last June, the Bush administration was still fighting any punitive action against a dictator whom the president now compares to Hitler. Assistant Secretary of State John Kelly testified vehemently against sanctions. Baghdad, he said, was "taking some modest steps in the right direction."

Sanctions were imposed, finally, after Iraq's Aug. 2 invasion of Kuwait.

Even Hitler never used poison gas against cities or armies, and the carnage from Saddam's chemical weapons is probably a hundred times Kuwait's death toll, which Amnesty International estimates at 500.

Two American presidents couldn't bring themselves to tell a barbarian that the use of poison gas -- outlawed in Geneva protocols in 1925 and honored by every nation since -- is not acceptable.

Now we are poised for a ground war, and the country's heart is in its mouth. Will Saddam use gas against our troops? For seven years, we assured him that gassing people is no big deal. If Saddam thinks he can get away with murder, Republicans encouraged him to do so.