THIS SPRING, when my son was approaching his 18th birthday and graduation from high school, he said he did not feel ready for college and wanted to do something else for a year or two. He asked my advice.

Any father of an adolescent son will realize how unusual this request was and how seriously I took the responsibility involved.

I thought a lot about the lives of the people I knew best -- the people of my own generation who reached their 18th birthdays during World War II and whose years between high school and college had been inrerrupted by military service. It seemed to me that most of them had been better off because of the interruption, that the maturity and purposefulness they brought with them to college made the experience of higher education meaningful to them in a way it often was not for the students of other generations.

So I said, why not join the Army or the Navy? My wife's reaction to this suggestion was negative, spiritedly negative. But, while a woman of strong views, she also believes in investigating all sides of a matter. She undertook an exhaustive survey among her friends, including the staff of the excellent school where she works. She reported that she could not find one person who agreed with me. Not one.

As she described their reaction -- almost all are intelligent, middle-class liberals, most in their thirties -- the triumph of the "From Here to Eternity" view of the military became clear: The service was full of intellectual clods, sadistic sergeants and incompetent officers. How could I dream of exposing my son to such an experience? Hadn't I seen what happened to poor Prewitt?

I had, but I had also been in the Army and known hundreds of others who served in the Air Force, Navy or Marines. The service can be as cruel as it was to Prewitt. It can be even worse -- remember My lai. But it can also be an important period of testing and growth.

Many of my wife's friends admire and recommend the Outward Bound experience for young people. Military basic training is often quite similar, but my wife's friends don't know about the similarity because, like most middle-class people of the Vietnam generation, they have had no actual military experience.

This means that they also don't know that my son, in addition to meeting some people he wouldn't like, would also find that untutored America is not an intellectual desert. There really are Hucks and Jims out there. They may not have read the right books (or, indeed, any books), but they can be funny and wise and good friends to have in the clutch.

Here is my Third Law of Politics: The number of parking tickets issued declines in direct proportion to the number of days remaining before the next municipal election.

Last year and the year before, Washingtonians could not park in an illegal place for more than a few minutes without having their cars towed away and paying a fine of $50 or more. Now that Mayor Barry faces reelection next year and indignant constituents are the last thing he needs, how many tow trucks have you seen lately?

The Democrats are being terribly irresponsible in simply attacking, without offering an alternative, the administration's efforts to face the coming problems with Social Security and federal pensions. Why not come up with a program that reflects the party's traditional concern for the poor but that is still economically feasible?

One way to do that would be to eliminate Social Security payments for people who do not need them. That would mean saying Social Security will no longer be treated as an unconditional insurance program, but as a program of insurance against need.

My rich Aunt Alice would no longer be able to use it for her trips to Europe but my poor Aunt Minnie would be taken care of.

As for federal pensions, one answer is to change the minimum retirement age for civilian employes from 55 to 65. Another is to have military employes, who can now retire as early as 38, wait until 55 or 60 unless they have suffered some physical disability.

When Carl Brown was running for a seat on the county commission of Jefferson County, he said he thought the $20,000 a year part-time job was overpaid and promised if elected to return $3,000 of his annual salary to the state. Brown won, but now the Kentucky Supreme Court has ruled that by offering to save the county $3,000, Brown violated a law prohibiting candidates from promising "things of value" in exchange for votes.

Judges are but one part of the powerful constituency that resists any reduction in the inflated salaries paid to many public employes. After all, judges are public employes too. So are congressmen. For reasons I don't fully understand, a lot of journalists are part of this constituency. The result is a lot of articles like the recent one in Time that proclaimed: "Frustrated career employes are leaving federal jobs in droves for better pay in the private sector."

This is quite simply untrue. Of the executives who leave the civil service, far more do so to retire -- under the generous pension plans offered by the government -- than to accept better pay in the private sector. Government salaries are in fact quite generous on the whole --just ask the federal employes who have lost their jobs under Reagan's outbacks how easy has it been to find better or even equal compensation on the outside.

As of Oct. 1, there will be 46,000 federal employes making $50,112. The administration wants to remove the amendment that limits their salary to that amount so that none of them will be denied the 4.8 percent increase given other civil servants.

The Administration also proposes to give all military personnel a 14 percent raise. What a waste in both cases! The real need is for selective increases given to people who can actually command higher salaries outside -- skilled enlisted men are an example -- but not to those who are making more than they could ever get in private business.

I love the feeling of escape one gets on a boat, so this summer I took a trip from New York around Nova Scotia and up the St. Lawrence River. The ship was a good one -- and not cheap. My wife and I had the minimum-rate inside cabin, but most of our shipmates had to be reasonably well-heeled to afford the other accommodations. They were definitely upper middle class. They were from all over the country. They were mostly courteous, considerate, easy to talk to.

But they were mostly bigots. And this reminded me of something many of us in Washington tend to forget. It is that much of the American upper middle class is still bigoted and that blacks and Jews still have good reason for concern.

Fear of bigotry can seem unreal in Washington or in other large cities where it is possible to have an entire circle of middle-class friends who are all open-minded on matters of race and religion. My trip reminded me that we still have a hell of a problem with prejudice, not just from Archie Bunkers, but from the country club set as well.

The conviction I encountered most often was that everyone on welfare -- meaning blacks, it became very clear -- was a welfare cheat. Maybe a third of them are welfare cheats. This is the truth my liberal friends won't face. But two-thirds of them are people who need help, and I very much fear that my friends on the cruise and the Reagan administration they have elected will continue to begrudge that help.