Iraq's Hussein, defeated in war, tries to put the pieces together

Iraqi President Saddam Hussein is trying to put the pieces together at home and abroad after defeat in his disastrous 21-month war with Iran.

At home he has made sweeping changes in both his Baath Party Command and in his Revolutionary Command Council (RCC). Having won reconfirmation as party leader, he has made the changes presumably to remove any waverers or critics at the top and to have men he feels he can rely on in key positions.

Abroad, he has announced completion of the withdrawal of the last Iraqi units from Iranian territory.

His immediate need, of course, is to preserve unchallenged his hold on the presidency, despite his egregious miscalculation in launching the war against Iran in September 1980. His rule has always been personal or one-man, and he has never shied away from the most ruthless countermeasures to deal with prospective foes or challengers.

Overall, his aim now is apparently to resume ''business as usual'' as though the war with Iran had not taken place. He is particularly keen that everything shall be in place in his capital, Baghdad, for the nonaligned summit due there in September. He is scheduled to assume leadership at the summit of the nonaligned movement for a three-year period.

But the Iranian religious leader, Ayatollah Khomeini, who displays deep personal animosity toward Saddam Hussein, is not willing to let the Iraqi President off that easily.

Within hours of the Iraqi announcement that the last Iraqi troops had pulled back to their side of the border, Baghdad was charging that the Iranians were still firing on them. The Iranians answered that the Iraqis had not, in fact, withdrawn but merely shifted to more advantageous positions.

Ayatollah Khomeini has said in the past that withdrawal of Iraqi troops would not be enough. He wanted Saddam Hussein brought to trial, the payment of up to $ 150 billion in reparations from Iraq, and the repatriation to Iraq of Iraqi Shia Muslims sympathetic to Iranian Shia fundamentalism who had been pushed across the border into Iran.

The Iranians apparently are keeping these options open - as well as the question of whether they, in turn, will send their troops across the border into Iraq.

Paradoxically, the Israeli invasion of Lebanon and the Israeli threat to the Palestine Liberation Organization are helping Saddam Hussein.

First, Syrian President Hafez Assad - the Iraqi President's archenemy in the Arab world and the only Arab leader openly to support Iran against Iraq - has suffered a crushing blow at Israel's hands in Lebanon.

Second, Ayatollah Khomeini - given his long rhetorical posturing as an intransigent anti-Zionist - cannot afford to be seen at this moment of danger to the Palestinians as too openly anti-Arab. To strike too ruthlessly against Iraq at this time could give that impression.

But the Ayatollah still has cards to play in a game of psychological warfare with Iraq. He can continue to lob shells at the Iraqis just to keep them guessing. He can quietly continue to try to subvert Iraq's Shia Muslim population against Saddam Hussein - a secularly inclined Sunni Muslim.

The Iraqi President, in his sweeping personnel changes at the top in Baghdad, dropped nine men from the RCC (which had had 17 members) and brought one new man on to it, Vice-President Taha Mohieddin Marouf.

Seven of the nine dropped from the RCC also lost their places on the Baath Party Command. Some of them were compensated with what sounded like sinecures by appointment as advisers to the Office of Popular Organizations.

Within the Cabinet, a new oil minister has been appointed: Qassem Ahmed Taqi.