President Reagan probably has the sympathetic understanding if not the good cheer of most Americans when he tells them that the economic recover ''is going to be slow.'' His argument that the country got into its present fix over a period of time and that it will therefore take time to correct mistakes of the past is hard to refute. Americans should know from past experience, moreover, that coming out of a recession too rapidly risks setting off another burst of inflation - the very condition the recession is meant to cure and, in this case, seems to be curing. So calling for gritty patience in the face of continuing adversity is not just a lame gesture.
At the same time it is clear that the slowness of the recovery is not the result of some carefully planned scenario. It is due to the still unprecedentedly high interest rates (even though they have dropped somewhat) which are inhibiting some areas of business, a factor the government did not have to deal with in previous recessions. And unless the government reduces the giant budget deficits projected for the next few years, interest rates may not come down enough to stimulate the economy adequately. Federal Reserve Board chairman Paul Volcker has just declared that additional tax increases and spending cuts will have to made next year to boost chances for a long-term recovery and that such moves would give the Fed more flexibility to ease up on the money supply in order to bring interest rates down.
Mr. Reagan is prepared to accept tax increases and vows to call for more spending cuts as well. But few think that deficits on the order of $140 billion annually can be reduced significantly without tackling the two largest categories of spending: entitlements and defense. Reform of social security and other entitlement programs is being looked at. But the President is disinclined to deal similarly with the military budget. He has even made a point of saying that he does not feel bound by the ceilings on military spending for 1984 and beyond that were set by Congress recently with his approval. This suggests he may be intending to ask even more money for defense.
This is bound to frustrate many people. It is not, after all, a matter of halting the needed defense buildup but simply of reducing the rate of increase in military expenditures. That is, seeking out the fat and waste in the defense budget with the same fervor as has been applied to trimming social programs. There is hardly an independent defense analyst who does not point to billions of dollars of waste in poorly chosen weapons, uncontrolled procurement, lax oversight of the defense industry, useless military bases. These are areas that also cry out for the ''courage'' the President enjoins upon Americans - political courage.
One source of sizable savings lies in putting a cap on nuclear arsenals. This is one reason the strategic arms and other negotiations are so important. The United States should be bending every effort to achieve agreements with the Soviet Union - an outcome that would not only reduce the awesome danger of nuclear war but free the superpowers to turn huge resources to civilian rather than military needs.
In this connection, it is surprising to hear that President Reagan apparently has no enthusiasm for a summit meeting with Leonid Brezhnev and indeed believes it is better to wait and deal with his successors. That seems a short-sighted and risky approach. First of all, it could mean waiting many years; no new Soviet leaderhip, even if one were to come to power soon, would plunge quickly into an arms control agreement. Secondly, there is nothing to assure that a new team in the Kremlin would be more disposed to conciliation; it could prove to be tougher than the relatively cautious crew in power now. Is it not wiser to deal with an adversary whose positions are already known? Unwillingness to pursue serious negotiations with Mr. Brezhnev only feeds the suspicion of some (including Europeans) that the administration does not really want a nuclear arms agreement and is simply spinning out the talks while it proceeds to gain clear nuclear ''superiority.''
Surely if the President is to make the US economy whole and vigorous once again, he will have to respond to what lawmakers, economists, business leaders - the American people in general - see as too high a military budget. They are not pacifists. They want a sturdy defense. But they know that, unless those deficits are brought under control, economic recovery will be impaired. And without the foundation of a strong economy - those mounting stockpiles of shiny arms could become irrelevant.