Strange, but there seems hardly a murmur of disapproval over Iran's invasion of Iraq. Can it be that the world is benumbed by the welter of territorial invasions in recent months and feeling helpless in the face of them? First Iraq invades Iran. Then the Argentines invade the Falklands. Then Israel invades Lebanon. Now the Iranians are reciprocating in a self-confident tit-for-tat reprisal. Surely peoples and governments everywhere ought to be alerted to what seems to be almost an epidemic of self-willed resort to violence. Indifference should not be allowed to deaden conscience or lessen determined efforts to resolve disputes by peaceful means.
In the case of Iran, few pretend to know what the Ayatollah Khomeini's objectives are. He is perceived as a militant religious leader bent on spreading the flames of revolutionary fundamentalism throughout the Muslim world. Indeed his religious fanaticism has stirred deep fears in Saudi Arabia and other nations of the Gulf region, threatening to eclipse the dangers they feel from Israel's military ascendancy.
Whether Khomeini can expect to help install a regime in Baghdad oriented toward Iraq's majority Shia population is open to question, however. To encircle the strategic town of Basra and cut off Iraq's lifeline to the Persian Gulf is one thing. To march on Baghdad in a full-scale assault is another. More realistically, the Iranians seem to be using military pressure to oust Saddam Hussein, broaden the Iraqi regime, and enable Iran to extract the maximum terms for settlement of the Iran-Iraq border issue. Even removing Saddam cannot be viewed as an easy goal, inasmuch as the Iraqi strongman has established a ruthless grip on the country and eliminated his opponents.
Perhaps, too, the prospects for a spread of fundamentalism are being exaggerated. It should be borne in mind that, as a result of the Islamic revival in Iran, other nations in the region have become more alert to its dangers. Egypt's new president, for instance, moved swiftly to curb the activities of the Islamic extremists. The Gulf states have gotten together to discuss their concerns, and their governments now are better able to deal with the threat. Some analysts believe that secularism is now sufficiently established in most countries of the area - Egypt, Syria, Iraq, Jordan, Oman, the Gulf states - and the modernization process far enough along that fundamentalism will not ignite.
This is not to underestimate the threat which Iran seems to pose in the region, however. Its successful defense against Iraq's foolish aggression and its reemergence as a military power - but a theocratic one - are bound to affect the standing of Saudi Arabia and others. The future is uncertain, to say the least.
In this unpredictable situation, and until the outlines of Iran's aims become clearer, the United States and other Western nations must necessarily tread cautiously. Washington's pledge of neutrality in the conflict assures that it will be able to keep open lines of communication with both nations and be in a position to try to effect a settlement of the dispute. At the same time the Reagan administration has prudently signalled Khomeini that the US is prepared to take ''appropriate'' steps to assure the territorial integrity of friendly nations in the region.
Even while waiting for the dust to settle, however, the governments of the West should take time to ponder the lessons of the Iran-Iraq war and other conflicts. Too much diplomatic energy is expended reacting to crises after they reach the stage of armed conflict and far too little addressing the problems which give rise to it. As MIT political scientist Lincoln Bloomfield noted recently, ''The crisis mentality has become a way of life. . . In our age of hardball politics, variegated ayatollahs, and out-of-control arms sales, less is invested each year in peacefully resolving disputes in advance than in a couple of Exocet missiles.''
How many wars can the world afford before the lesson is learned?