What has happened in Poland raises perhaps the most complex set of choices ever cast up by a political-ideological upheaval on the fault line that runs beneath the East-West divide.

Each time in the past when there has been a seismic tremor at the juncture where capitalism and communism discordantly meet, the United States has found--as have its adversaries in the Kremlin--that there are no easy choices.

For all the anti-communistic fervor of the Eisenhower years, which the Reagan administration looks back on enviously, John Foster Dulles could not (and never planned to) deliver physically on his rhetoric of "liberation" and "rollback" in Eastern Europe.

The Reagan administration remembers that, and it is not vulnerable to any similar expectations from the people of Poland. Nevertheless, the United States in other ways feels the violent tremors inside Poland, which have shaken the entire Soviet bloc and, in their denouement, are now bound to shake the West.

Politically, the United States is impaled in Poland by the American News Analysis News Analysis leadership of the Western alliance, and doubly so by special American-Polish ties which date back to the 18th century.

Diplomatically, it is impaled by the outcome in Poland because it is joined with the Soviet Union in an elusive search in Geneva for a measure of nuclear arms control, which Western Europeans now see as a touchstone for their survival, and perhaps for the cohesion of the West as well.

By no means least of all, the United States and its allies are enmeshed in a financial web which makes communist Poland a crippled debtor of Western capitalism to the tune of $26 billion, and makes Western governments and banks financial hostages to the future of Poland.

No single nation has control of the script for the next act in this unfinished drama. It cannot automatically repeat what happened in the East German uprising of 1953; in the bloody Hungarian revolution of 1956 and in the political revolt in Poland that same year; in the Soviet destruction of the "Czechoslovak summer" in 1968, or in Poland's forceful suppression in 1970 of its recurrent food riots, when Lech Walesa and others learned the lessons which enabled them, in August, 1980, to mount their bold challenge to Soviet rule.

For now the complexities of the Polish situation have multiplied; so has the price on both sides, East and West, for action or inaction.

It would take a diplomatic giant--or an extraordinarily lucky novice--to find a path through this morass with any degree of confidence. Even then, no amount of wisdom or luck could assure that all the competing forces involved, inside and outside Poland, would interact in accordance with the most cunning grand design.

The Reagan administration does not, and cannot, claim any diplomatic giant in its ranks.

It was positioned early in its term, as the Carter administration had been, for what most diplomats later came to recognize as the least likely probability: a bolt-out-of-the-blue frontal assault, with Soviet and other Warsaw Pact armies leaping into action to crush independent unions, free speech, pluralistic politics, and all the audacious ventures of the Solidarity movement.

To counter such a crude thrust, it was comparatively easy for the Carter administration to gain general agreement inside the North Atlantic Treaty Organization for non-military retaliatory measures: notably, diplomatic and economic reprisals against the Soviet Union. That has remained the benchmark for coordinated NATO response to flagrant Soviet intervention in Poland.

The secrecy surrounding details of the allied contingency plan has helped, not unintentionally, to muffle doubts about how loyally that plan actually would be fulfilled, "if the balloon goes up."

Balloons, in diplomatic or military context, however, never rise exactly in conformity with any adversary's contingency plan. That in effect was conceded by Secretary of State Alexander M. Haig Jr. when he acknowledged Sunday that while allied intelligence was well aware of escalating tension in Poland, the West as a whole had been caught off guard by the crackdown in Poland at dawn that day.

The elaborate enforcement of martial law in Poland and the even more elaborate nationalistic rationale which accompanied it obviously took days, probably weeks, of preparation and coordination. It is not surprising, therefore, that formulating a plausible response to it by an alliance not noted these days for dutifully following anyone's lead, is no overnight task.

For the crisis-untested and frequently openly divided Reagan administration, it is difficult to imagine an international problem that could confront it with more complex requirements for diplomatic subtlety.