• U.S.

Defense: The Space Bomb

3 minute read
TIME

For 14 months U.S. space and intelligence experts have intensively analyzed a secret series of Soviet orbital experiments, suspecting from the start that Moscow was building a new space weapon. Last week, in a surprise Pentagon press conference, Defense Secretary McNamara confirmed that assumption.

Though the evidence is not yet definitive, he said, the tests clearly “relate to the possible development by the Soviet Union of a Fractional Orbital Bombing System, or FOBS.”

This conclusion was reached by Washington after tracking eleven Soviet launchings since Sept. 17, 1966, in which attempts were made to return pay loads to the ground within less than one complete orbit. The success of the Russian experiments has been such, McNamara indicated, that an orbital bombing system capable of dropping nuclear warheads on America may well be operational some time next year.

Vital Difference. Basically, FOBS can pack the punch of some ICBMs—with a vital difference. Shot into a low orbit of 100 miles, the FOBS rocket slows and ejects its nuclear bomb before completing its route around the globe. This combination would prevent anti-ballistic missile radar (BMEWS), presently the U.S.’s main screen against surprise attack, from ascertaining the point of impact until the rocket “deboosts”-about three minutes and 500 miles from target. By contrast, the U.S. now has a 15-minute warning against ICBMs. Experts say that the Soviet FOBS could carry the maximum payload equivalent of 3,000,000 tons of TNT, twice that of the submarine-launched U.S. Polaris missile.

McNamara did his best to minimize the impact of his disclosure. He argued that FOBS is considerably less accurate than ICBMs, which was the primary factor in the U.S. decision against building its own FOBS several years ago. Further, he said, the U.S. has developed an over-the-horizon radar capable of tracking a missile from the moment of blast-off at Russia’s Tyuratam ICBM complex; the new radar will be fully operational in February and will give Washington 30 minutes’ warning of a potential attack. The new three-stage Spartan anti-ballistic missile will also increase U.S. ability to intercept any incoming missile.

Timing. The Pentagon’s current impression is that the Soviet orbital bomb is principally designed against vulnerable American bomber bases. While admitting that there is no foolproof defense against massive Soviet ICBM and FOBS attacks on cities, McNamara argued, as is his wont, that the best deterrent continues to be the immense target killing powers of the ground-based U.S. ICBM arsenal, the roughly 600 nuclear-armed strategic bombers and 650 Polaris missiles.

Since the U.S. had suspected Soviet FOBS’ development for so long, why did Washington wait until last week to make it official? One answer is that it was only in the past few weeks that analysts felt the evidence was strong enough. Also, with congressional hearings this week on the nation’s missile defense system, McNamara obviously wanted to use his own platform for such a significant disclosure. Finally, no doubt, Washington felt that Moscow might make the announcement during this week’s 50th-anniversary celebrations of the Soviet Revolution, and thus create the shattering impression that the U.S. was now wide open to destruction from outer space.

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