Although it's not a best seller, annual defense report is well read. Weinberger explains and justifies 3 percent budget increase

Action in this paperback involves weapons, bad guys, and extremely large sums of money. But with its lack of love interest and plain blue cover, the book is unlikely to be a best seller, even if its author is the secretary of defense. The book is the annual report to Congress by Pentagon chief Caspar Weinberger. Issued each year at budget proposal time, it explains and justifies United States military programs.

The fiscal 1988 report strongly defends as affordable the Reagan administration's plans for a 3 percent defense budget increase. It implies that cutting Pentagon spending is tantamount to yielding to the forces of darkness.

``Anyone who says we cannot afford to do what we must to keep our freedom is halfway along the road to losing it,'' says the report.

The book also notes that in recent years the US has been outspending the Soviet Union on new weapons. US military procurement passed the Soviet Union's in 1984. This is the result not only of the Reagan administration's buildup, but of a leveling off in Soviet defense spending over the last decade.

The total Soviet weapons stock is still worth 30 percent more than that of the US, Secretary Weinberger writes.

Among other themes to be gleaned from the report:

US forces should exploit chinks in the Soviet's military armor.

This approach to weaponry, dubbed ``competitive strategies'' by Weinberger, means that the US should emphasize areas where its technological edge is greatest.

Antisubmarine warfare is one such area, the report says.

Another area is the ``Stealth'' radar-masking technology. A new generation of US bombers, fighters, and cruise missiles means that ``the Soviets will be forced to make an enormous investment in new defensive systems over a span of many years,'' according to Weinberger.

Low-intensity conflict is becoming an increasingly important threat to US interests.

Native insurgencies, Soviet-sponsored subversion, and terrorism are all on the rise in the third world, says a section of the report devoted to the subject.

Though these threats often are more than just a military problem, the report says, they have clear military dimensions and the US should develop forces able to fight low-intensity war, such as special forces.

Latin America is one area where the US traditionally has had a small military presence yet is now involved in a number of low-intensity conflicts. The annual report claims that if left unchecked, Cuban and Nicaraguan military buildups ``and the spread of communist-backed insurgency could eventually force the United States to reorient substantial forces to protect its interests in the region.''

The Strategic Defense Initiative is itself being defended in increasingly strong terms.

In past years the annual report talked about SDI as a research program perfectly proper in light of Soviet research in the same area. For fiscal 1988 the report talks about SDI more as a defense pillar for the '90s. SDI would make the world safer, the report says, not because it would be leakproof, but because it would make Soviet planners less sure they would succeed with any nuclear attack.

``We will never give it up,'' says the report of SDI.

The report says the Soviets already vigorously pursue defense programs such as hardened intercontinental ballistic missile silos, a vast force of interceptor aircraft, and an operational antiballistic missile system around Moscow.

But it also implies that these efforts would not be effective. ``While the Soviets apparently seek a capability to combine offensive strikes and defensive preparations'' to limit the damage a US response to a Soviet nuclear attack would do, ``they do not have that capability, and are unlikely to believe that they do,'' the report says.