Children's rhymes were the last thing on the mind of Secretary of State Dean Acheson when, preoccupied with Stalin's expansion into Central Europe, he spoke at the National Press Club in Washington on Jan. 12, 1950. In the speech, which had been approved by the White House, Acheson outlined America's ``defense perimeter'' in the Pacific, clearly leaving out the Korean peninsula. Five months later, Kim Il Sung's armies, confident that Washington wouldn't intervene, invaded South Korea. Thus began the Korean War, a conflict in which thousands of Americans lost their lives.

Acheson's blunder came to mind recently while reading a July 7 article in The New York Times in which an unidentified Clinton-administration official talked about ``a conscious decision in this administration to do what needs to be done.'' The Times ominously explained that to mean ``American officials say they are now determined to go forward [with their commitment to relaxing U.S. sanctions against Fidel Castro's regime] even if Mr. Castro responds by cracking down on dissent.''

Ironically, the statement coincides with a reappraisal of Canada's longstanding policy of ``constructive engagement'' with Havana. Despite tourism, trade and foreign aid, Castro remains oblivious to Canada's pleadings on behalf of human rights. Canada's most influential media have called for a tougher stand vis a vis Castro, and a not-so-subtle message to that effect was delivered recently: The new Cuban ambassador presented credentials in Ottawa in an elegant room in which almost all of the chairs set up for official guests were empty.

The new U.S. policy -- assuming the report is accurate -- is at odds with Americans' humanitarian impulse. It could have serious consequences for U.S. policy in the Americas because President Clinton's hemispheric policy is predicated on support for democracy, human rights and the rule of law.

One can only wonder what the consequences would have been had the United States told Moscow that, regardless of its mistreatment of human-rights dissidents, Washington cooperation would remain on track. Or what might have been Poland's fate had the United States signaled to Gen. Wojciech Jaruzelski that it was all right for him to crack down on dissents. Instead, to its credit, the Reagan administration imposed trade sanctions on Warsaw when it tried to crack down on Solidarity.

Years earlier Jimmy Carter had electrified the world with his call for worldwide respect for human rights. Due both to its source and its content, the idea that greater repression in Cuba will not impact U.S. policy undermines Clinton's publicly stated views and Secretary of State Madeline Albright's repeated and principled efforts to mobilize international support for the victims of Castro's repression.

Like Kim Il Sung almost 50 years ago, Castro will interpret the statements attributed to the Clinton administration as a green light for whatever steps he takes. Also, foreign governments that would rather not confront Castro's rhetoric (at the United Nations in Geneva, Cuban diplomats labeled those concerned about human rights in Cuba ``lackeys'' of the United States) now will find it even easier to turn a deaf ear to the Cuban people's cries for help.

Is it really in America's national interest to broadcast such fickleness to our enemies, repeating Acheson's error? It certainly is not. However, this is exactly what is occurring when senior Clinton-administration officials tell Castro that U.S. policy will not be affected by a crackdown on Cuba's courageous and beleaguered opposition.

How can the Clinton administration claim that it cares about the Cuban people's fate while erasing whatever remaining uncertainty Castro may have about America's intentions? How many ways are there to spell disaster? Several weeks have passed, but it is not too late for the President to order an investigation and reaffirm his commitment to supporting the Cuban people's aspirations for freedom.