Doubt about John Sununu's future usefulness was raised in the minds of George Bush's political A-team members last week when they heard him react with anger to Sen. Phil Gramm's (R-Texas) plea for Republican unity.

One insider arrived at a gathering of Bush loyalists certain that Richard Darman must go as budget director; he left certain that Chief of Staff Sununu also must go. "I believed we had to get John back with conservatives and Congress," another veteran of the '88 campaign told us. "After seeing the way he treats a senator, I'm not so sure that's possible."

Sununu is crucial to the outcome of a midterm policy debate about whether President Bush should pursue a reform agenda, including tax changes to fight the recession. Sununu entered the White House as resident conservative and functioned that way until the disastrous budget fight. Since then, he has been Bush's raging bull, denouncing erstwhile comrades on the right.

One presidential aide compares Sununu's labor for Darman's budget deal to Col. Nicholson's obsession with building the bridge on the River Kwai demanded by his Japanese captors -- a good man captivated by an evil project. With Sununu's bridge now complete, conservatives had hoped he would rejoin them.

That goal seems more distant after what happened Wednesday night in a private dining room at the J. W. Marriott Hotel, two blocks from the White House. The purpose of the affair was to introduce William J. Bennett, Sununu's handpicked choice as Republican national chairman, to Bush political regulars (about 30 of them, from Cabinet members to private citizens). Typically, Sununu controlled and dominated the evening.

Even colleagues accustomed to his robust style were taken aback. So little could be said without Sununu interrupting and contradicting that naturally voluble politicos were silent.

When Gramm talked about cooperation with Republicans and Congress, the chief of staff delivered a denunciation of Capitol Hill. When political consultant Roger Ailes suggested the president had a problem "communicating" his position on the budget and the Persian Gulf, Sununu snapped back that the White House was communicating just fine; the problem was the news media's refusal to report what the president said.

There was a disconnect between on the one hand, Sununu and Darman, tight as brothers, and on the other, just about everybody else. The mood around the table reflected anxiety about the president's and his party's political fortunes after the divisive budget fight, the looming recession and the dangerous crisis in the Gulf. Most were silent, but GOP national finance chairman Larry Bathgate painted a picture of economic distress caused, he said, by Republican-appointed financial regulators.

In contrast, as described by one diner, "John was into denial on everything": the budget deal was excellent; the Republicans had not lost the tax issue because, as he knew from New Hampshire, people only care about income taxes and not excises; the recession would be short and shallow, ending about the time economists acknowledged it had begun.

Sununu's decision to limit the dinner for Bennett to supporters of Bush's 1988 nomination was questionable with Bush on the threshold of the third year of his presidency, but not even all the loyalists made the guest list. The politics of exclusion, not inclusion, prevailed. No member of the House was present. The name of House Minority Whip Newt Gingrich (R-Ga.) was not spoken, but all knew he was the bull's-eye for Sununu's darts.

Simultaneously at a Capitol Hill restaurant, Gingrich was telling reporters that Darman should resign because of his opposition to conservative reform. Perceiving correctly that this was no idle threat, the brainy budget director shows signs of running scared, converting Disdainful Dick to Charmin' Darman. On the afternoon of the dinner, he was sweetness and light at a Domestic Policy Council meeting, embracing reforms he had ridiculed a week earlier. On the next day, he telephoned to ask for a meeting with Gingrich and his ally, Rep. Vin Weber (R-Minn.).

No such diplomacy has come from Sununu. He has yet to reopen communications with Gingrich, with whom he talked daily before their budget rupture. No word has passed between them, not even on Election Night when Gingrich barely retained his seat in Georgia. From the White House comes word that the chief is on the rampage against Republican National Committee Chief of Staff Mary Matalin, a quintessential Bush loyalist, because she is too close to Gingrich.

The positive note at Sununu's dinner was Bennett's performance. Those present who had known him only from unfavorable press accounts describing a blowhard were impressed by his tact in separating himself from Sununu without giving offense. Such finesse will be needed for the new party leader to redirect the raging bull's charges from Republican to Democratic targets and turn his dynamism from denying problems to solving them.