AT this Christmastime the hearts of Americans are singing. The Iron Curtain is crumbling. Presidents Bush and Gorbachev are talking like friends. Peace may not be here - but it seems closer. There are a few Scrooges. Paul Nitze, arms negotiator extraordinaire, is one. He talked to reporters over breakfast the morning Mr. Bush embarked for home after the Malta summit. The summit was mainly a public-relations triumph for the president, Mr. Nitze said. He added that Mr. Bush had forgotten he was dealing with the Soviet system, not just with Mikhail Gorbachev - who is ``tottering,'' and ``may have a difficult time surviving the winter.''
Former Defense Secretary Caspar Weinberger dropped by our breakfast table the next morning to do his part to dampen down the post-summit euphoria.
``Not very much was accomplished, actually,'' he said. He, too, thought that Bush was depending too much on Gorbachev. His forecast for Gorbachev's ability to stay on his job was ``probably no more than a year.''
Meanwhile, Vice President Quayle was putting his own downspin on Malta, saying the Soviet government was still ``totalitarian'' and that Soviet foreign policy hadn't really changed. The only real change going on in the Soviet Union was economic reform, emanating out of necessity, he said.
The president went out of his way in advance to tell the media not to expect too much. After Malta he emphasized that this was not the end of the cold war. But he had declared as the summit ended: ``We stand at the threshold of a brand new era of US-Soviet relations.'' That raised expectations.
What the public had been told would be a get-acquainted session had gone beyond that. More than anything, Bush had given Gorbachev encouragement in his effort to buoy the Soviet economy. He held out hope for more foreign investment and better trade status for the USSR.
Also, Bush agreed to a June deadline for a strategic arms accord with the USSR. This brought criticism from Nitze, who was senior arms control adviser to President Reagan. He said the president ``showed a lack of understanding in setting such deadlines. Deadlines are not a way to negotiate successfully. It was improvident. The United States must settle issues before setting dates - not the other way around.''
But the public impression of the Malta meeting was of the two top world leaders getting together and bringing global stability - and peace - several steps closer. Despite Bush's effort in Brussels to cool post-summit expectations, the American people have taken the event as a Christmas gift.
Of course, some politicians see big reductions in defense spending on the horizon. That's the Christmas gift they see. Indeed, Defense Secretary Richard Cheney reports that some congressional leaders are telling him they are going to insist on as much as $l80 billion in cuts over the next few years.
Talk in Congress has the defense cuts offsetting the budget deficit. But Mr. Weinberger believes that any trims from defense ``will go into politically popular domestic programs.'' He also thinks ``a lot of jobs will be lost'' if defense spending is slashed.
What would happen with a greatly reduced defense budget? Weinberger said that if the reduction came too fast and was too deep it would damage the economy but ``wouldn't wreck it.'' While the negative impact on the economy should be taken into account, ``there is really only one reason for resisting these big defense reductions: We must keep our guard up,'' he added.
There is evidence, reflected in polls, that the US public sees historic change at work in Europe. Americans hope this aroused spirit of freedom will continue to control events. And this they might well call the spirit of Christmas, l989.