SIENA, ITALY. — Siena, Italy HERE WHERE late-20th-century man gawks amid the relics of a Renaissance civilization from which we have lamentably declined, the Persian Gulf seems remote and unimportant. Saddam Hussein is a very bad man, but there is nothing original in cruelty or power struggle. Renaissance Siena was fully acquainted with both.
Elimination of the Iraqi dictator -- an objective not easily obtained -- would change the world for the better, but not by much. The American temptation, always yielded to, is identification of the currently prominent villain as fulcrum of all evil.
Policy planning is then devoted not to improvement of a mediocre situation but to its redemption by means of the villain's overthrow: thus America's obsessions with the Iraqi dictator, a Panamanian general, a Libyan colonel, an Iranian ayatollah, a Palestinian terrorist, a Vietnamese revolutionary and a Chinese one -- before that, with a Cuban revolutionary-nationalist. Even before that was Stalin, the only serious case among them all; and he died in his bed.
Meanwhile history has gone on much as it would have without our obsessions or most of these individuals. What they represented: revolution, counterrevolution, nationalism, ideological and sectarian intoxication -- exists today just as it existed before.
Thus the reactionary-isolationist camp in the current American debate has a case when it argues that the United States has no interest in the gulf sufficient to justify war on the scale that is likely to result from an attack on Iraq. Israel does, of course. But Israeli interests are not necessarily U.S. interests. The ''surgical strike'' argument is contemptible obfuscation, or the product of sheer and culpable ignorance of war.
An analogy is the Korean War. There, as in the gulf, the United States resisted aggression, under U.N. auspices which it had itself vigorously promoted. North Korea and China, like Iraq, fielded peasant armies, capably commanded, well equipped in low- and medium-technology weaponry adapted to a punishing environment. Their armies were eventually defeated, or stalemated -- not by surgical strikes, but by brutal manslaughter, costing more U.S. casualties than the American public finally was willing to tolerate (54,000 dead and more than 100,000 wounded -- at that only a tenth of the casualties thought to have been sustained by the Koreans and Chinese).
Aggression was not curbed. It went on: Iraq's in Kuwait, Libya's in Chad, the U.S.S.R.'s in Afghanistan, North Vietnam's to reunite Vietnam, the PLO's and Israel's in Lebanon, Argentina's -- our own, when politically convenient, as Saddam Hussein likes to remind the world.
The underlying rationale for U.S. intervention in Korea was that North Korea's invasion of the south had been ordered by Stalin as the first move in a Third World War. It proved to be wrong. The intervention merely settled that Korea would not be united under Kim Il Sung. This was a worthy achievement but not one the American public would have gone to war for.
Thus the importance of the current debate in Washington and the American press. What is the appropriate principle-versus-casualties equation? What equation would be acceptable in the gulf if even the best outcome leaves the Middle East seething with hostilities? But then what are the costs of committing this enormous military force to the gulf and bringing it home again with Saddam Hussein still in power and Kuwait still a part of Iraq? That seems to this writer the decisive consideration. But my confidence in success is not great.
The elimination of Saddam Hussein and the destruction of Iraq's present capacity to manufacture weapons of mass destruction can be achieved, at a price. The second objective can only transiently be assured. Every industrializing country now possesses the possibility of making such weapons.
It certainly is worth demonstrating that international aggression invites multilateral retaliation. Demonstration that the friendship of the United States is worth having, and that its wrath is terrible and efficient, could provide a calming influence in Third World turbulence. On the other hand, should military matters go badly -- as they did twice, very badly, in Korea -- the opposite lessons would be taught.
War is an instrument of political policy and is justifiable only when that policy is intelligent and achievable. It is not a way to settle the question of good and evil, as a notable Italian 400 years ago would have told both George Bush and the newspaper pundits in New York and Washington who strive for the president's mind (or soul?).
''How we live is so far removed from how we ought to live, that he who abandons what is done for what ought to be done, will rather learn to bring about his own ruin than his preservation.'' I am not ordinarily the purveyor of Machiavellian amorality; but the point is a pertinent one.
So, eminently, is the fact that the wars and internal political struggles of the Italian city-states of the Renaissance, as passionate in their time as gulf and Middle East are for us today, proved to be of negligible consequence for us, or for Italy, today. Only Renaissance art, and thought, endure.