President Hafez Assad's outspoken criticism of the Reagan administration was unusual, but not his message that Syria preferred a bloody nose on the battlefield to being seen as knuckling under to foreign pressure.

That constant theme is one of the key reasons he has succeeded since 1970 in ruling a country previously known for its almost annual coups or attempted coups.

"We stick to a rule which says nobody can strike Syria and evade punishment," he said in his interview with The Washington Post. "The past years have proved that Syria accepts no humiliation and fears no danger, however big it is, when it concerns its dignity and the dignity of the Arab nation."

Decoded, that means that Syria considers itself the center of the Arab world and has used regional crises to extract often grudgingly provided diplomatic, political and financial support from more timorous Arab regimes.

Under Assad, Syria has chalked up an uncanny record for snapping back from battlefield drubbings and seemingly disastrous crises.

Whether Syria will bounce back from its current troubles is not yet clear. Despite earlier Israeli government accusations and American and British suspicions of Syrian involvement in recent acts of terrorism in Europe, by midweek a western envoy said "the war threat seems to be over" for the time being, at least with Israel.

But American officials are watching closely the British investigation into the attempted bombing of an El Al airliner in London on April 17 that had many American passengers on board. If evidence of Syrian involvement were to be proved, there could well be American or joint retaliation.

Yet even if the threat of punitive action over this incident does subside, Syria is no longer riding the crest of victory in the region.

At home, Assad acknowledged that antiregime bombings have killed 144 Syrians and wounded 149 others in a series of recent bus and train attacks.

The economy is so squeezed that foreign exchange has virtually disappeared and Syrians are getting used to shortages of even their much beloved coffee.

The largesse of Kuwait, Saudi Arabia and the other oil-producing states of the Persian Gulf has diminished sharply -- in part, according to diplomats, because of their own depleted coffers, in part to exert pressure on Syria to drop its alliance with Iran and thus help end the almost six-year-old Iran-Iraq war.

Next door in Lebanon, which remains the regime's number one foreign policy problem, Syria's seeming success in forcing the main rival militias to submerge their differences and accept a "Pax Syriana" have proved a will-o'-the-wisp.

Assad admitted as much by acknowledging that Syria would accept "amendments" to the now marooned, Syrian-brokered tripartite agreement among Druze, Shiite Moslem and Christian militias last year. That accord sought to enshrine a special role for Syria in Lebanon's constitutional structure.

Nor did Assad seek to minimize his frustration with the tactical alliance in Beirut now linking armed Palestinians loyal to Chairman Yasser Arafat of the Palestine Liberation Organization -- whom Syria has sought to topple -- and the Iranian-influenced Shiites of the fundamentalist Hezbollah.

Taken together, the Palestinians and Hezbollah constitute as much a thorn in Syria's side as do the Christian militias that upset the tripartite agreement and Syrian hopes of dominating the situation.

Assad's admission of difficulties in persuading Hezbollah to release western hostages also raises questions about his encouraging the Palestinians and the pro-Iranian Shiite fundamentalists as a counterweight to the more moderate Amal militia in southern Lebanon.

Similarly, his claim that his troops in Lebanon's Bekaa Valley could not control Abu Nidal's terrorist training camp there also reflected a much diminished role for Syria so near its own border. So, too, did recent clashes in the Bekaa city of Baalbek between Syrian soldiers and Hezbollah militiamen.

Even Assad's success last fall in forcing King Hussein of Jordan to recant publicly for having harbored anti-Assad members of the fundamentalist Moslem Brotherhood in Jordan has not borne all the fruit Syria wished.

Jordan has yet to jettison its alliances with Iraq or Egypt, Syria's rivals for Arab leadership, or to break with Arafat despite the collapse of the Jordan-PLO peace initiative in February.

It was perhaps for these reasons that Assad has delivered mixed messages on Lebanon, criticizing the United States for allegedly backing Lebanese President Amin Gemayel's defiance of the tripartite agreement and appealing to Washington to stop its "obstruction" there.

But despite this, and Syrian charges that the United States went along with the Israeli invasion of Lebanon in 1982, diplomats throughout the Arab world are speculating that Assad would also like to mend his fences with Washington -- not so much to balance his alliance with the Soviet Union as to find a way out of what he called the "quagmire" of Lebanon.