Last week, the Senate Appropriations subcommittee on defense voted 12 to 1 to pare down our military presence in Europe by 23,000 troops. The colleagues explained their near-unanimity variously, as might be expected from such a varied group of statesmen, but beneath the sonorous elucidations there lurked one disturbing constant, to wit: the growing irresolution of conservatives in the Senate.

Both there and in the House conservatives are yielding to the bullheaded protests of their liberal opposites. So readily do they now collapse that one begins to suspect that yesteryear's calls for increased defense and a diet for the American milch cow state issued not from a sound vision of America's needs but from a hunch about how to get elected.

Conservatives on the Hill are showing less and less inclination to lay into those blowsy social programs that transfer so much of the nation's wealth from the productive middle class to the pocketbooks of the welfare professionals. There are very good reasons to cut many of the so-called human resources programs. Some have not worked, and many more are abundant with fraud and waste.

Of course, few solons on Capitol Hill have any idea how the government is spending the taxpayers' dollars. Over the past 21 years, allocations for human resources have climbed from $30.7 billion (28.8 percent of the federal budget) to an estimated $385.7 billion (50.9 percent of the federal budget). That is an increase of 1,156 percent. Not even a Congress exuberant with Einsteins could comprehend and oversee such a vast increase in programs and boodle.

There are no Einsteins on Capitol Hill, and the chaos in managing American government grows. Last week the White House put Counselor to the President Edwin Meese in charge of a six-year plan to rationalize Washington's administrative practices, but not even the pious liberals in town believe the thing really possible.

The government has 350 different payroll systems and 325 accounting systems, all basically incompatible. Washington's advocates of the milch cow state believe in efficiency as Brezhnev's colleagues believe in the Marxist pipe dream; both are beside the point. Yet every time a conservative scrutinizes the flab in our human resources budget, the liberal brethren squeal.

So the conservatives now turn their scrutiny to the military budget. Doing so does not inflame the liberals, who dream of imminent doom but live as though the world were abounding with smile buttons. The conservative economizers are being penny-wise and pound-foolish. Twenty years ago, JFK was spending about half our budget on defense. In fiscal 1983, even with the Reagan administration's desired increases, the military's slice of the budget will only increase to approximately 29.9 percent. Is the world more blissful today than it was in the early 1960s? Ask an Afghan.

When the Reagan administration took office, it was bequeathed a military in an advanced state of decrepitude, wanting in spare parts, ordnance, equipment readiness, training readiness and manpower. In the past 20 months, there has been marked improvement in all areas. Yet America remains weak, and when America is weak, Americans are unsafe

Some of the conservatives voted as they did last week for reasons that have a superficial plausibility to them. Sen. Jake Garn wanted to notify the Europeans that they are not carrying their load in the NATO alliance and that by entering into commerce with the Soviets they are "aiding and abetting the emeny with high-tech technology." The concerns are sound, but not the vote. Our troops are serving our defense purpose in Europe. For over three decades, they have helped to keep the Soviets relatively quiescent and away from our shores. Merely because our extravagant domestic spending has created a budgetary pinch and because our European allies are as difficult as a fabulous prima donna, we ought not to junk the military policies that have served us so well.

Despite all the liberals' jeremiads about war and the military-industrial complex, the fact remains that for nearly four decades we have not been in the kind of war the liberals fret over. Those who want to revert to the military posture of the 1930s and before might recall that in this century, before the rise of the infamous military-industrial complex, we averaged a world war every 20 years.