It's possible the spirit of "bipartisanship" that lately has been gripping official Washington will move President-elect Bush to take a somewhat slower approach to certain big-ticket items on his agenda. Let me eliminate one from contention right now: missile defense.

The reason is as simple as it is alarming. The long-range missile threat to America has actually been getting worse since a 1998 congressional commission-chaired by Secretary of Defense-designate Donald Rumsfeld-first warned of this danger to U.S. security. A new global threat assessment by the National Intelligence Council says that the risk of the United States being attacked by a missile carrying chemical, biological or nuclear warheads is greater today than during most of the Cold War.

And U.S. intelligence sources expect it will get worse, with potential terrorist attacks getting "increasingly sophisticated and designed to achieve mass casualties."

Interestingly, some of the most vociferous critics of a U.S. missile shield are the same governments working the hardest to beef up their own arsenals. China, for example, has been particularly harsh in denouncing a U.S. national missile defense. Yet officials there made a point of testing the DF-31, a missile that could reach California, during a recent visit by Gen. Henry Shelton, chairman of the Joint Chiefs of Staff.

Which is why all Americans should be glad that Retired Army Gen. Colin Powell, tapped by President-elect Bush to be Secretary of State, endorsed missile defense as "an essential part of our overall strategic force posture" in his acceptance speech.

Here are a couple of pointers for the new administration, courtesy of Heritage missile-defense expert Baker Spring:

• Affirm America's decision to deploy a national missile defense. There's this wrong-headed but persistent notion that the president still has to decide whether we'll deploy a missile defense. Wrong. That decision was made over a year ago, when Congress passed and President Clinton signed the National Missile Defense Act of 1999, making it official U.S. policy to build a system "as soon as is technologically possible." What the president has to do now is figure out which system he wants to deploy: land-based, sea-based, space-based, or some combination.

• Declare the 1972 Anti-Ballistic Missile Treaty null and void. If there's any single reason Americans are unprotected today from missile attack, it's because the United States still clings to the ABM treaty, signed nearly 30 years ago with a country that no longer exists: the Soviet Union. The treaty prohibited the construction of any national missile-defense systems. But with our former treaty partner gone, the agreement is no longer in force. It's time to recognize that our defense needs have shifted dramatically since the Cold War.

• Begin testing a sea-based missile defense. Such a system would offer several advantages over the land-based system proposed by President Clinton. Because sea-based interceptors can be positioned on existing Navy Aegis cruisers, this system would be cheaper to build: $8 billion, instead of $20 billion. It also would take less time to build, with a targeted deployment date of 2005, rather than 2007. And because it would be based on ships, it would be mobile and cover a far greater area more efficiently than a single site in Alaska.

But the most important thing is to act-and now. Because the other side is hardly standing still.

Edwin Feulner is president of The Heritage Foundation, a Washington-based public policy research institute.