If his administration follows through with the aplomb shown in the formation stages of its Persian Gulf reflagging, Ronald Reagan may find himself in a no-lose situation despite the Democratic crusade to kill the plan.

Even before the first Kuwaiti tanker raised the Stars and Stripes or a Navy escort ship has had its first test from Iranian Silkworm missiles or Revolutionary Guard speedboats, Reagan's hard-nosed Gulf tactics have tripped up Soviet Mideast ambitions. They have also given new hope to friendly Arab states, so long ignored by the administration.

The president has been told by U.S. intelligence that Iran is not likely to retaliate quickly. When reprisals come, they will probably be tangential. No clear fingerprints would be left by targeting hostages in Lebanon or taking subversive actions against Kuwait or Bahrain. But under current White House planning, even such once-removed reprisals may produce an American military response that will shock the Ayatollah Khomeini.

Such plans come from a newly confident mood in the Reagan White House, derived in part from national sentiments stirred by Lt. Col. Oliver North's testimony. ''This country will stand and cheer if Iran gives the president a real reason, not some phony excuse, to go after the ayatollah,'' a source with access to high Reagan officials told us. ''Reagan knows this better than anyone.''

The immense naval power the United States has assembled in the Persian Gulf and east of the Strait of Hormuz in the Gulf of Oman answers secret Soviet pressure on Kuwait late last year. But at that time, the administration was in the grip of its arms-for-hostages caper and could not respond.

With the White House secretly sending missiles to Iran, there was then no U.S. answer to the Soviet decision to give Kuwait the tanker guarantees against Iran that had been asked of Washington. There was only silence here until the Iran arms deal exploded last November, formally ending the clandestine overture to Tehran.

Then, at the lowest point of his presidency, Reagan came to grips with the fact the Kremlin was moving in on Kuwait while his administration was playing futile games with Iran. The president insisted on immersing himself in the new policy. Kept in the dark about many of the most momentous events when the Iran-contra schemes were being worked out, Reagan personally chaired and controlled three long National Security Council meetings that led to reflagging.

That put him on the ground floor of the Persian Gulf crisis. While he was ignorant about the diversion of Iran arms profits to the contras, Reagan himself made the decision to preempt Moscow from playing Kuwait's protector. He soon witnessed its result: cancellation at the last minute of a high-level Soviet mission to Kuwait, scheduled for March.

That visit was supposed to put finishing touches on the Soviet plan to safeguard Kuwaiti oil shipments. Arab friends tipped the United States that Moscow would follow up the good with the bad. In return for Soviet naval protection, Kuwait would be pressured to back the Kremlin's plan for ending its invasion of Afghanistan on Moscow's terms. If Moslem Kuwait had been forced to succumb to that pressure, it would have demonstrated U.S. impotence once again and would have further undermined this country throughout the Islamic and Arab worlds.

U.S. combat plans to meet possible Iranian retaliation for the reflagging are under tight wraps, but they run the gamut from verbal warnings to naval shelling to air attack. Calibrated response has not always been this president's forte, a fact most aptly demonstrated by its inconclusive flailing in Lebanon after the Marine barracks were blown up by a truck-bomb in 1983.

But the careful structuring of the reflagging decision is different, a fact Democratic leaders may not appreciate. Sen. Albert Gore Jr. is the only Democratic presidential candidate who has publicly stated his support of the reflagging decision, while the rest of his party has searched for ways to undermine the policy.

That puts Reagan in a political catbird seat. With the nation riding high on the wave of patriotism from Ollie North's remarkable performance on the witness stand, the president operates from a strong foundation for any confrontation with Khomeini. Nobody close to him today doubts that if he does what he wants -- and what may well be needed as the Iranian propaganda apparatus fulminates -- the arms-for-hostages fiasco may become history sooner than seemed possible.