A few months ago the United States scrapped its 38-year-old defense agreement with New Zealand.

Washington did so because that country insisted on knowing whether U.S. ships were nuclear-armed or nuclear-powered before permitting them to use New Zealand ports.Now the U.S. may be forced to get tough with a number of other allies for the same reason.

The Philippines could be on the verge of adopting a new law barring the entry of any nuclear-armed or powered ship, plane, or overland vehicle. Likewise, Denmark is about to vote on a resolution requiring warships entering Danish territorial waters to disclose whether they carry nuclear weapons.

What short-sighted folly!

The U.S., Britain, and other nuclear nations can't identify which of their ships carry nuclear weapons without targeting those vessels for first-strike destruction in any nuclear conflict.

Nor can the U.S. and Britain reasonably be expected to extend their protection to nations whose demands render that protection less effective.

Fortunately, the U.S. has some leverage it can use against such unreasonable demands. The Philippines, for example, is heavily dependent on U.S. financial assistance to help its debt-burdened economy. If the Philippines won't back off from its proposal to bar nuclear ships, planes, and vehicles, Washington should have no qualms about cutting back on such assistance.

Likewise, if Denmark won't see the light on this score, it should be read out of NATO just as New Zealand was ousted from the ANZUS alliance for its stance on nuclear ships.

In any event, some of America's allies clearly need to learn that when they enjoy the benefits of an integrated defense system, they also must share the risks.