"We must use our machine-guns . . . to free Jerusalem. . . . The day will come that everyone wishes to be a resident of (Jerusalem). . . . Israel must be banished from the face of the earth."

Those jolly exhortations are printed around the edges of a brightly colored map of the Middle East. Copies by now should be in the hands of every member of Congress and the key people at the State Department and the Pentagon.

The words alone would suggest an Israeli effort to unmask the true purposes of the Palestine Liberation Organization. But the distributor in this instance is Nizar Hamdoon, the ambassador to the United States from Iraq. And his target is Islamic fundamentalism in general, and the Iranian regime of the Ayatollah Khomeini in particular.

Hamdoon clms (experts who have seen the document have no reason to doubt him) that the map was taken from captured Iranian revolutionary guards. He picked up a copy while visiting the battle front at the time of the latest, failed Iranian offensive last month.

The war between Iraq and Iran has raged on and off for 41/2 years with neither side demonstrating the ability to win conclusively. Yet Hamdoon is not alone in his concern over the larger aims of the ruling Shiite fundamentalists in Iran. The tracing by U.S. intelligence of devastating terrorist acts in Lebanon through Syria to Iran suggests that the Iranians don't have to win the war to be a menace to the area. Shiite extremists are an active threat in Lebanon. American as well as Iraqi analysts share a worry that Iran may take out its frustrations in the war with Iraq by making a move on Kuwait.

Thus a prominent American Arabist finds Hamdoon's map "very interesting," if only in the sense that it brings the fanatic public rhetoric of Islamic fundamentalism into tight focus. That Israel is on the Iranian hit list is no surprise; so are almost all of America's Arab friends, most notably the monarchies and sheikdoms sitting on the vital oil resources of the Persian Gulf. But Iranian fundamentalist indoctrination has to be running deep when the ayatollah's Revolutionary Guards are carrying into battle so explicit a statement of their mission.

You would expect the map to show its five, arrowheaded, green and yellow bands sweeping out of Iran and converging on Baghdad. But you might not expect to see three huge arrows thrusting westward at Jerusalem, or to find the Iranian future for the Persian Gulf conveyed by designation of Saudi Arabia on the map as "Arabstan."

The conclusion that official Washington is being invited to draw from this bit of evidence is that Iraq stands as a vital bulwark defending American interests in the Middle East -- including not only the Moslem elements, but Israel. What then?

Iraq's immediate objective is modest, Hamdoon insists. With its Moscow connection, its dependence on Soviet arms, and its professed devotion to nonalignment, Iraq has no expectations of material U.S. support. But it would welcome a political and diplomatic shift of U.S. policy away from strict "neutrality." Specifically it would like the United States to use its influence on Europeans, Japan and others of its friends who continue to sell Iran trucks, small boats, light aircraft and other items that contribute to the Iranian war effort.

With an eye to a post-Khomeini Iran, the Reagan administration has so far been careful not to choose sides. So a conspicuous "tilt" to Iraq now is unlikely. U.S. policy, which has yet to be put to a test by the inconclusive ebb and flow of battle, is a negative: it doesn't want Iraq to lose.

But the Iraqi campaign, as evidenced by Hamdoon's map, reflects a positive side to U.S.-Iraqi relations that few would have forecast as recently as four years ago. Then Iraq was seen as the instigator of the war with Iran, the shelterer and fomenter of terrorism, the Arab state that friends of Israel and the Israelis themselves most love to hate.

By the time full diplomatic relations were reestablished between the United States and Iraq last November, after a 17-year break, Iraq had noticeably tempered its public stance on a solution of the Arab-Israeli-Palestinian conflict. It had largely rid itself of the "terrorist" image. It had also moved closer to restoring relations with Egypt, and generally identified itself more clearly with the "moderate" Arab camp.

That it should now be presenting itself, for whatever reasons of expediency, as a credible line of defense against threats to Israel's security is one more sign of that never-ending Middle East "potential" for change.