TIRED OF sanctions, confrontations and isolation? Seeking another legacy than that of terrorist? Playing a new role? Who can tell just why "the Leader," Libya's Moammar Gadhafi, now seeks to transform himself in world opinion from an authentic rogue to a respecter of law and comity among nations? That is, to partly transform himself, for reportedly he continues to contribute to terrorism at points in Africa and to hold on to serious weaponry he accumulated in a 30-year revolutionary career.

Known to the West in his days of defiance chiefly as a terrorist, President Gadhafi won Communist and Third World favor for challenging the United States and Europe and for embracing the liberation movements of southern Africa. A breakthrough of some sort came just this year in his handover for European trial of two operatives accused of the bombing of Pan Am 103 in 1988. He also paid $40 million in the bombing of a French airliner. These gestures earned him release from most of the air-travel sanctions imposed by the U.N. Security Council. From there Mr. Gadhafi now reaches for further international respectability as an advocate of conflict resolution in Africa and of that continent's integration into the global economy.

The United States imposed its own, tougher sanctions against Libya during Mr. Gadhafi's duels with Ronald Reagan. Less driven by commercial pressures than the Europeans and more driven by a loathing of terrorism, Washington has its own standards for finally lifting sanctions. These include Libya's cooperation at the presumably forthcoming trial of the Pan Am 103 suspects, the acknowledgment and appropriate compensation of past terrorist acts and the termination of support for all forms of terrorism now.

To provide reasonable assurances that Libya does not possess weapons of mass destruction would also no doubt help Moammar Gadhafi secure the friendly access to the West that he spurned 30 years ago and that he desires today.