The negotiation between the two superpowers for a new agreement putting a brake on the development of nuclear missiles looks to the outsider like a prolonged and secret chess game. If it ends in a statemate with no agreement, so what? We will hear dire predictions, but we've heard dire predictions before.

Two hard facts get in the way of that easy brush-off of the game being played in Moscow with Secretary of State Cyrus Vance as U.S. team captain. The first is money.

Without an agreement and with an all-out arms race, the United States would have to spend an additional $20 billion over a 10-year period for nuclear weaponry. And while the two players would be sitting on much more massive mountain of sudden death, they would be in precisely the same position as to total strength.

That $20 billion would be added on to the defense bill and it would proportionately swell the total budget. The nation's defense today takes 23 percent of that budget. It would take proportionately more if that monstrous chess game ends in stalemate.

Failure to point up these figures has been a weakness of those working for a SALT II agreement. One of the few who has added up the figures as they come from the Pentagon is Rep. Les Aspin (D-Wis.) They have received too little attention and particularly from those absorbed in abstruse arguments over the relative capacities of weapons that are an outgrowth of technological genius and understood lonly by their makers.

At the end of the 10-year period the United States would have an estimated 2,300 missile launchers and the Soviet Union 3,100. But what with differences in targeting, duality of warheads and other factors, that would be rough equivalence. Essentially nothing would have been changed in the 10-year period despite the spending by both sides of something more than $40 billion.

Except for those who want to put out the darkest possible case, no official concerned with the negotiation has ever doubted American capability to respond to a soviet first strike. Capability to respond to such a strike, if it should ever come, is part of the deterent power in the delicate balance between the two giants.

The second fact that cannot be ignored is the reaction among America's allies if a SALT II agreement should be reached, looking into lthe future for a more substantial SALT III, and then the agreement should fail of ratification by the Senate. As now contemplated by Vance and arms negotiator Paul Warnke, the sequence will be as follows.

An agreement embodied in a treaty will be reached toward the end of June. Requiring careful study and inveitably long debate, it will not be submitted to the Senate with the congressional election coming on.

Will it be ratified by the requisite two-thirds vote? One measure is the opinion that Horst Ehmke took back to Bonn with him after a mission to Washington, sampling opinion in both the executive branch and Congress.

Ehmke, who is deputy chairman of the Social Democratic faction in the Bundestag and former chief of staff to Chancellor Helmut Schmidt, came here as the result of a telephone conversation between Schmidt and President Carter. They had agreed that it was time to try to iron out some of the differences that had grown up with increasing acerbity between the two capitals.

In his soundings on Capitol Hill, Ehmke found considerable pessimism about ratification of an arms-limitation treaty. That was confirmed by opinion he heard in the State Department and the White House. Just before he returned to Bonn he left no uncertainty about what failure on SALT would mean in Europe:

"It would be an unqualified disaster. It would mean a resumption of the cold war and the end of hopes for a peaceful world for the foreseeable future."

We are not alone. Our European allies are already deeply troubled by the administration's inability to restrain oil consumption and stop the downward spin of the dollar. A start has been made with the sale of Fort Knox gold, but there is still a long way to go, and Europe is deeply concerned over the outcome.