HIS POST-SUMMIT press conference in Houston was pretty much the compleat George Bush.

The gracious host, the foreign-policy buff, the seeker of small goals, the loyal father, the defensive environmentalist, all those facets of his personality and character were on display. So were his good manners, his strong family feelings, his emotionalism.

Stylistically, it was appealing and helped explain his high poll standings. Substantively, it was no great shakes, and there were glaring contradictions on aid to the Soviet Union and China and on the environment. But he was immensely likable. Even while he was declaring war on the environmentalists, he remembered to welcome them to Houston.

In the assembly hall of the Brown Convention Center, he was in his element. Houston -- the place he has decided he is really from -- had come through for him, competing successfully in the range of its hospitality with Venice, Paris, London and other summit sites. None of those cities ever matched the center's Texas-size press buffet, which ran six different food lines around the clock and handed out free cigarettes, newspapers and toothpaste. The spirit of Houston was epitomized in a buffet vignette: a Japanese correspondent eating raw fish as two waitresses hovered over him, one with red wine, the other with white.

Bush got raves from his fellow-summiteers, who were feted at museums and mansions. Most important to him, he had pulled them back from the brink of what to him was precipitate action -- as is most action -- on aid to Mikhail Gorbachev and serious steps on global warming.

Germany will go its own way on financial aid to the Soviets and on reducing carbon dioxide. Studies will be done. Bush appreciates the stalling. He is exceptionally well suited to preside over a gathering which ratified the new egalitarianism among Western nations. He is too well brought up to revel in the rampant "We're Number One"-ism of the Reagan years, and his natural diffidence helps him to feel comfortable in a reduced role.

He seems genuinely not to mind. For some reason, he hates to declare the end of the Cold War. In his introductory remarks he referred to the first postwar summit -- but when challenged about not calling the shots any more, he said it's a different world, or more precisely, it's a free world.

But Bush could not make sense of his minimalist policies towards the Soviets and China. Moscow, it seems, will be spurred to reform if the West withholds money. But China, which is being considered for World Bank loans and recently had its most-favored-nation status renewed, will apparently be kinder and gentler if it does get money.

Bush knew he would be asked about his son, Neil, who has been caught up in the net of the S&L scandal. Even so, his face reddened when it came. But his answer, which plainly had been thought out in part, was an exemplary expression of love, anguish, principle and civic virtue. He would not intervene, and he had talked to no official involved in the case -- "but what father wouldn't express a certain confidence in the honor of his son?"

The president painted an attractive picture of the Bush family rallying round a member in trouble. His other three sons, he said, "want to go to the barricades."

Said Bush, "I say, you calm down now. We're in a different role now. You can't react like you would if your brother was picked on in a street fight."

He was so churned up that his feeling spilled over to his next answer. Before he knew what he was doing, he had launched into a tirade against the environmentalists who had traveled to Texas to torment him.

It was bad enough that they had mortified him with an environmental report card on which the United States and Canada were tied for fourth place. "Their grading system is absolutely, essentially absurd," fumed the environmental president. It was worse, apparently, that they attacked his new best friend, West German Chancellor Helmut Kohl, for caving in on a call to reduce carbon-dioxide emissions. And the "purists" didn't vote for him, anyway, and he is not going to pander to them, either.

He became incoherent. He had had "cloakroom conversations" with some of the Group of 7 -- the industrial nations attending the summit -- and they were not going to change their policies to satisfy the demands of the "loudest voices" outside. Of course they wouldn't. Kohl and Margaret Thatcher, too, already agree with the environmentalists.

What made his position "absolutely, essentially absurd" however, was the thought that Kohl and Thatcher are deliberately planning to throw thousands of people out of work, which Bush insists will be the consequence if serious steps are taken to avert global warming.

The Japanese were waving around blueprints for the next 50 years. The Germans have a 15-year plan in place. Bush never thinks beyond the next election. He may be a happy president, but he will not be a great one.