Old cold warriors never die, they just get more paranoid. A prime example is the request by Sen. Trent Lott, R-Miss. - and the assent by Sen. John Warner, R-Va. - for the Senate Armed Services Committee to investigate allegations that China is undermining U.S. security by attempting to gain control of shipping through the strategic Panama Canal. Nothing could be more preposterous.

Some conservatives argue that Panama Ports Co., which won a long-term contract to operate the port facilities at both ends of the canal, and the owner of its Hong Kong-based affiliate Hutchison-Whampoa Ltd. have links to China's People's Liberation Army and intelligence services.Adm. Thomas Moorer, former chairman of the Joint Chiefs of Staff, goes even further: ''Hutchison-Whampoa controls countless ports around the world. My specific concern is that this company is controlled by the Communist Chinese. And they have virtually accomplished, without a single shot being fired, a strong hold on the Panama Canal.''

The alarmists also note that 10 percent of Panama Ports is owned by China Resources Enterprise, the commercial arm of China's Ministry of Trade and Economic Cooperation. Sen. Fred Thompson, R-Tenn., has called China Resources an agent of espionage for China.

Yet do the Hutchison-Whampoa owner's links to the Chinese military and intelligence services and the Chinese government's ownership stake in Panama Ports necessarily constitute an insidious geopolitical plot? The contract by a shipping company to operate port facilities may simply be designed to make money.

The Chinese government and military have routinely been engaged in business activities overseas to turn a profit - for example, in the food and clothing industries. Because he felt that commercial distractions undermined the Chinese military's effectiveness, Jiang Zemin, China's leader, recently ordered it to get out of such activities.

If business ventures have such a detrimental effect on China's military readiness, perhaps the United States should encourage more, not fewer.

Furthermore, the Panama Canal Commission insists that Panama Ports cannot determine which ships can transit the canal. In fact, according to the Panama Canal Treaty of 1977 - which ends U.S. military presence in Panama in December - U.S. military vessels will continue to have priority for passage.

Even if the Chinese business activities in Panama have a geopolitical motivation, they will likely have little strategic effect.

After the demise of the Soviet Union, the Panama Canal is much less important for U.S. security. Today, the U.S. Atlantic and Pacific fleets each can maintain overwhelming dominance in their respective regions. Even during the Cold War, the Navy's capital ships, the aircraft carriers, were too large to fit through the canal.

The Chinese would probably be reluctant to close a waterway that they also use for commerce. In the worst case - if Panama Ports blocks the canal or refuses U.S. Navy vessels passage - the world's most powerful naval forces could open up the waterway rapidly. Even conservatives admit that the treaty allows the United States to intervene if access to the canal is blocked.

And exactly what would the ''China threat'' faction have the U.S. government do about the situation? The sovereign government of Panama has entered into a long-term contract with a private company for operation of the waterway.

What right does the U.S. government have to veto commercial agreements by other governments? Should the United States invade Panama again to assuage the fears of those who would like China to be the enemy in a new Cold War?

According to Gen. Barry McCaffrey, former head of the U.S. Southern Command when it was based in Panama and now the U.S. anti-drug czar, ''We don't have vital national security interests in Panama.''

And a report written in 1997 by a member of the staff of Jesse Helms, chairman of the Senate Foreign Relations Committee, also seemed to discount threats to the canal. After extensive discussions with U.S. and Panamanian officials, the staffer concluded, ''All those interviewed for this report state the HPH's development of the two ports does not translate into a direct national security threat to the Panama Canal.''

Finally, the timing of the alarmists' shrill warnings is suspicious. The search for threats to a man-made body of water that has declined in strategic importance is a desperate attempt to roll back the treaty-mandated withdrawal, to take place in December, of an unneeded U.S. military presence.

Imperialist cold warriors just cannot bear to give up Panama. They will have postpartum depression, but the rest of us can celebrate the rebirth of Panama without a humiliating and anachronistic colonial presence on its territory.