THE ARGUMENT over the future of Alaska has reached a critical point. After quickly -- and predictably -- deteriorating into a brawl on the Senate floor, the debate was taken behind closed doors. There a group of senators is trying to work out a compromise. If they succeed, the Alaska lands issues may finally be settled this year. If they don't, the argument is likely to drag on unresolved for decades.

This is hardly the ideal way for the Senate to handle one of the most important environmental bills of the century. The fundamental question involved is this: how much land in Alaska is the federal government going to continue to control and to what degree should that land be protected? Unfortunately, the Senate has delayed so long in taking up this legislation that it is running out of time. One Alaskan senator, Mike Gravel, has said he will do anything he can to stop passage of any bill. The other senator, Ted Stevens, has been threatening to do the same unless the final bill is more to his liking than the versions sought by the Carter administratioin and environmental groups. Given the opportunities for dealy in the Senate rules, they might succeed.

That result, peculiarly, is sought by die-hards on both sides of this debate. Some Alaskans, for reasons that defy rationality, think their interests will be better served if no bill is passed. Some of the environmental groups think -- and they are quite right in this -- that they win more from no legislation than they will from any legislation Sen. Stevens is likely to accept. More Alaskan land would be locked up more tightly under the past and promised administrative actions of President Carter and Secretary of the Interior Andrus than under any proposal now pending in Congress.

The trouble is that if Congress does not act this year, it may never act at all. Institutional tolerance for continued hassling over even so major a subject is wearing thin, and there is a possibility that after the November election there will be a revised cast of characters who would have to start at the beginning.

If Congress doesn't pass an Alaska lands bill of some kind, the future of the state will be left in the hands of the courts. They will decide -- after, no doubt, years of litigation -- on the legality of the Carter administration's actions. That would be unfair to Alaska in the short run because its economy would be unnecessarily harmed, and it could be a catastrophe for Alaska's interests in the long run. It would also be unfair to those environmentalists who have fought to strike an equitable balance between development and preservation in Alaska's vast open spaces.

There is some room for maneuver between the bill of the Senate energy committee and amendments to it proposed by Sen. Paul Tsongas. Both sides would be better off if they tried to get the good of it.