At a time when the President is being buffeted by Congress, it is important to note that his defeats are only partial. Mr. Reagan has a way of changing the question being asked on the Hill - and around the country as well. The question now being asked by even old-time spenders is, ''How much can we cut expenditures?'' What a change from the main question in Congress for the last 50 years: ''How much can we spend in order to solve domestic problems?''
Mr. Reagan got almost everything he wanted from Congress in the way of spending reductions in the first two years, though of course he negotiated for more. As a former union leader he knows that he must ask for more to get what he really is after.
The challenge to Mr. Reagan now comes from some of the moderate Republicans as well as the enlarged Democratic ranks, and it focuses on the defense budget where the President already has been defeated on his request for a 10 percent increase in spending.
But what is not given much attention is the fact that Mr. Reagan, elected in part on his promise to build up the military, has again changed the question. His foes, in and out of Congress, no longer ask: ''How much can we cut back on defense spending?'' Instead they ask: ''How much can we cut back on Reagan's defense-spending proposal?''
The fact is that Mr. Reagan is already presiding over a massive defense buildup. At the minimum defense spending will go up 5 per-cent in fiscal 1984. The President's request for a 10 percent increase was, again, mainly a bargaining position. His counsellor, Ed Meese, now says that the President would be willing to accept the difference between 5 and 10; say, 7 1/2 percent. Mr. Reagan may not get that, but he probably will get at least 6 per-cent.
Here the President's continuing strong political position enters into the picture. With Mr. Reagan sending out new signals indicating he will run again, the Democrats in Congress who will be up in 1984 are listening - and will listen as they vote: They don't want to ask for voters' support with a record which Mr. Reagan will underscore has been too resistant to his defense buildup. Politicians who read polls calculate that the public at large wants the buildup to continue - nuclear-freeze advocates notwithstanding.
A new CBS-New York Times poll shows those who approve and those who disapprove of Mr. Reagan's performance running about equal - roughly 40 percent. This is the kind of support that Mr. Carter was getting four years ago when he decided that things were going poorly enough to warrant a reshaping of his presidency.
If Mr. Carter found the going rough politically why should Reagan, with comparable public support, still be riding so high?
Mr. Reagan has not chalked up any sparkling achievements that would match the accomplishments of Mr. Carter - the Israel-Egypt treaty, the Panama Canal treaty , nor-malization of relations with China. Perhaps an economic resurgence will be considered Mr. Reagan's great contribution - if joblessness drops, interest rates decline, inflation stays down, and the economy as a whole continues to grow and stays healthy.
Yet Mr. Reagan remains strong at the helm, while Mr. Carter was, at this point in his presidency, widely viewed as a less-than-strong leader - although one who also was personally well liked.
Polls find that Mr. Reagan's strength, along with his personal appeal, lies in what the public perceives as his consistency - in the unvarying way he attacks economic problems and in his persistent, tough stance in dealing with the Soviets.
Mr. Reagan has changed the question about himself too in recent weeks. The question has been: ''How much more time does Reagan have to turn the economy around before he loses favor with the public?'' Now, with an economy that clearly is getting better, that question seemes to have faded. Now the question is simply: ''Will Reagan run again?'' And to that question the President is almost at the point of announcing that his answer is ''yes.''