The conflict over President Carter's human-rights program broke into an embarrassing boil on Aug. 3 when one of the nation's best Asian friends, Philippine Foreign Minister Carlos P. Romulo, boycotted Assistant Secretary of State Patricia M. Derian's brief appearance at a meeting here of U.S. Asian allies.

As Carter's human-rights spearpoint, Derian wields a sharp weapon, which drew blood on her visit to Manila last year. "She was rude to President Marcos," one ranking diplomat told us. "Romulo was boycotting her here as an individual, not as a U.S. government official."

Allies of Derian insist she was only doing her duty in Manila. They insist, too, that the wave of new congressional laws requiring strict human-rights accountability before U.S. arms, police equipment or ordinary commercial goods can be approved for export are making her job more complex than it used to be.

True or not, Derian and her rapidly expanding Office of Human Rights and Humanitarian Affairs are under attack - still largely subterranean - from the administration's political and economic specialists, from trade experts in the Commerce Department and from U.S. manufacturers. Thus far, the effect on the dauntless Derian, a veteran of the Mississippi civil-rights wars, is not noticeable.

On July 17 she hired liberal arms specialist Stephen Cohen from the State Department's policy-planning staff to supervise all security-assistance exports (arms and police equipment) from the human-rights standpoint. Cohen was the 10th top professional named to Derian's staff. At least two more are wanted.

Human-rights activists at State argue that new laws linking arms sales to human rights made the hiring of Cohen mandatory. But the Pentagon, jealous about its arms-control powers, is angered. Cohen's new role is also resented by some officials in the office of Lucy Benson, under secretary of state for security assistance.

More to the point Derian's zeal as a political activist. High-ranking diplomats report that in pushing the human-rights goals of Jimmy Carter, Derian is blunt. She informed the highest leaders of at least one foreign country with a poor human-rights record that, as the only assistant secretary of state sworn in by Carter himself, she possesses special clout. Insiders say she is the only assistant secretary who rates a regularly scheduled private weekly session with Secretary of State Cyrus Vance.

Some sins attributed to her may be exaggerated. For example, consider the notorious case of the $411 worth of steel groin protectors and helmets for riot police in Indonesia (which has human-rights problem but sells the United States 9 percent of all our imported oil). In fact, that deal was approved Aug. 4 after a delay of a mere two weeks.

But Mark Schneider, Derian's top aide and a former legislative assistant to Sen. Edward Kennedy (D-Mass.), apparently disapproved the deal. His intials, "M.S," appear on a confidential bureaucratic memorandum on which a lower-ranking official had written "no go" for the groin protectors. Indeed, the higher-up decision to overrule Schneider may have resulted from press inquiries, including our own, over the fate of Indonesia's request.

Those "protectors" are significant (except for those who wear them) only as a symbol of how encompassing the U.S. human-rights role has become. The larger problem is agonizing delays in getting Derian's approval for big, lucrative, commercial deals between U.S. manufacturers and foreign buyers in countries found guilty of human wrongs.

More than $600 million worth of American exports to Argentina (including $270 million for Allis-Chalmers generators) has been held up more than four months. The dozen U.S. producers all need Export-Import Bank financing. An additional half-billion dollars in military sales is in the same "hold" category, with no assurance that export licenses will be granted.

"Argentina is looking to Europe and Japan, even to the Soviet Union, for other sources for this stuff," a State Department economic expert told us. "Once these trade patterns change they tend to stay changed."

Although both the military and commercial portions of those potential sales to Argentina are restricted by new human-rights laws that limit Derian's discretion, she and her mushrooming empire at State seem to want more, not fewer, restraints. That is clear from the initials "M.S." on the original decision to reject the groin protectors.

Such zeal has led Derian into deep trouble with the Philippines in the past. It could lead her into trouble with the White House in the near future.