The assassination attempts, mass deportations and angry rhetoric in Iraq today are for the country's leaders a disquieting throwback to the embattled early years following seizure of power by the Arab Socialist Baath Party in 1968.

Despite Baghdad's pretensions to Arab and Third World leadership, such as its effort in late 1978 to rally Arab opposition to Egypt's impending peace treaty with Israel, the Iraqi Baathists are showing signs of settling for mere survival.

President Saddam Hussein still formally follows a policy of calculated flexibility and seems in no hurry to return to the self-imposed isloation that formerly always made Iraq the Arab world's odd man out.

Two years ago, Iraq's pretensions to Middle East leadership were based not just on its potential -- oil reserves second only to Saudi Arabia, a disciplined and motivated ruling party, sufficient if salt-drenched land and a sizeable population -- but also on the weakness of its rivals.

Suddenly, geopolitics seemed to have singled out Iraq for greatness: a regional role as protector of the oil of Arab states in the Persian Gulf from the encroachments of Iran's Islamic revolution.

Yet, for those with long memories, it was as if an effort was being made to turn the clock back two decades, to the time before the 1958 military coup had swept away the British-backed monarchy and murdered prime minister Nuri Said. The West had set up the so-called Baghdad Pack linking Pakistan, Iran, Iraq, Britain and the United States in an alliance aimed at stemming Egyptian president Gamal Abdel Nasser's brand of revolution.

All but forgotten in the reworked Baghdad-as-bulwark theories has been Iraq's postrevolutionary record -- at least 10 coups or attempted coups, two armed rebellions, a full-scale civil war and an ever-restive Shiite Moslem majority.

Also overlooked in such calculations are the regime's bristling nationalism, its fixation with its sovereignty and its determination to maintain pure revolutionary credentials in playing host to the 1982 nonaligned summit conference.

Despite an admirable record on corruption (by oil-rich nations' standards, at least), massive efforts on education, industrialization, roads and housing, Iraq seethes with rumors of political instability.

In April, grenades were tossed at Deputy Prime Minister Tariq Aziz, the only Christian on the ruling Revolutionary Command Council. Last year, there were disturbances in the cities of Kerbala and Najaf, where important Shiite shrines are located.

Iraqi Kurds and Turkomands reportedly have been arrested -- national minorities that have been restive in neighboring Iran as well.

The regime has responded by expelling some 20,000 Shiite Moslems, most of them officially described as Iranian passport holders despite indications that some Iraqi nationals also were involved.

In the steady deterioration of their relations, border clashes gave way to unsubstantiated Iranian claims that Iraq had killed Ayatollah Mohammed Bakr Sadr, a Shiite leader who had been under house arrest since June 1979. b

Some influential Iraquis argue that it is the Iranian revolution's anarchy that poses the greatest threat to the region's established regimes.

Nowhere are the incumbents more vulnerable than in Iraq, which is run by Sunni Moslems increasingly under fire from Iran's Shiites, who are angered at their Iraqi brothers' alleged second-class citizen status.

In addition to problems with Iran, Baghdad's relations with Baathist rival Syria have worsened.

Egypt's military defection obliged Syria in 1978 to respond favorably to Iraq's call for unity despite the long history of bad blood between the rival Baath parties in Damascus and Baghdad.

But since last year relations between the two capitals have relapsed into Iraqi accusations that Syria fomented an abortive coup here and Baghdad's boasting that it backs the increasingly serious domestic opposition in Syria.

Nor have Iraqi efforts at improving relations with its Arab Gulf neighbors shown much tangible progress, although these weak, conservative regimes prefer Baghdad's current mood of cooperation to the past record of confrontation and subversion.

The 1979 security arrangements between verbally revolutionary Iraq and the Saudi monarchy, born of commonly perceived dangers from Iran, does not seem to have gone beyond the low-level police cooperations.

Since the Grand Mosque seizure in Mecca last November, the Saudis have become more wary of Iraqi ties, according to diplomats. Rising Iraqi political influence in Saudi Arabia could be interpreted as indirect support for the younger princes in the Saudi royal family who are said to favor lessened dependence on the United States.

Neither the United States nor the ruling Saudi princes are believed to be in any hurry to encourage such tendencies, especially since no one doubts Iraq's single-minded determination to dominate the Persian Gulf if given even the slightest encouragement.

Iraq's pretensions to gulf overlordship were deflated last October when Saudi Arabia pointedly did not invite Iraq -- but did invite Oman -- to a special conference in Taif to discuss regional security. Iraq had singled out Oman for criticism for welcoming an American military presence on its territory.

To the Iraqi leadership, there is no difference between the American and Soviet presence in the region because Soviet bases in South Yemen have been matched by Oman's offer to extend facilities to the United States.

Although the United States remains Iraq's number one enemy because of its support for arch-enemy israel -- known here ony as "the Zionist entity" -- Iraq has grown increasingly suspicious of the Soviets.

Iraqi leaders contemptuously dismiss Ethiopia and South Yemen for "selling themselves to the Soviets" and began worrying about Afghanistan not just last December, but in April 1978 at the time of the first pro-Moscow coup.

Despite the 1972 treaty of friendship and cooperation with the Soviet Union -- kept alive largely to ensure military spare parts -- the Iraqi leadership wears no blinkers.

"We consider the Soviets lost 50 percent of their good will here because of Afghanistan," said Naim Haddad of the Revolutionary Command Council.

About the only bright spot for Iraq is its relationship with Western Europe, pioneered by France in the early 1970s when Soviet influence here was at its zenith.

Haddad said recently, "We think some Europeans are beginning to understand, because of the region's oil.

"Their machines cannot run without oil and Arab nation needs European technology," he said. "Our interests coincide . . . so Europe can get rid of its American nightmare and enjoy independence."