WIN OR LOSE, the natural-gas bill is going to have an immense impact on American foreign policy and American standing in the world. If the bill is defeated, that will be read by other nations as a signal that Congress rejects President Carter's energy commitments to this country's allies. If the bill is enacted, it will mean that the United States is at last acting to curb its voracious imports of foreign fuel.

The implications of this decision go bar beyong the price of natural gas. If there is no action now, Europe and Japan fear, the enormous American imports will drive prices still higher and create shortages of conventional fuels in the next decade. The prospect of shortages becomes, in turn, an incentive to other governments to experiment with plutonium breeder reactors to generate electricity. But the spread of the plutonium technology makes it harder to control the proliferation of nuclear weapons. Few Americans see any connection between natural-gas prices and nuclear proliferation, but abroad the perspective is very different.

The natural-gas bill is, of course, the principal survivor of the famous energy program that Mr. Carter announced 17 months ago. None of it has been enacted. The idea of a heavier tax on gasoline was killed by the House at an early stage. The big tax on crude oil has been permanently ditched. Of the other fragments left lying around, some will be useful but all are minor. The exception is this gas bill, which, having been passed in very different forms in the House and Senate, has emerged from nearly a year of negotiation between them. It is a final, last-chance compromise that has now come to the floor of the Senate.

Some of the independence gas producers are fighting it vehemently on grounds that it is too complicated. Compared with what? Those gas producers are operating under the mistaken assumption that, if they beat the compromise, Congress will then promptly deregulate gas prices altogether. In fact, gas pricing would be left to the same authorities that control it now: the federal regulators and the courts. The gas compromise may be complex, but it is vastly preferable to the mindless and endless complexity, uncertainty and expense of the present regulatory system.

On the other side of the issue, some of the consumers' organizations argue that the compromise bill will cost consumers billions of dollars. Again, compared with what? Under continued regulation, gas prices will rise in the future just as they have risen in the past. If the regulators keep gas prices lower than oil prices, shortage of gas will continue. To meet the shortages, gas companies will import increasing amounts of foreign gas. Directly or indirectly, the consumer will pay for that imported gas - which will cost far more than the maximum prices permitted to American gas producers.

It is important not to overstate the benefits of the natural-gas bill. By raising prices it will tend to encourage conservation and exploration in this country and to discourage imports. But it will do those things only very gradually. It is only a fragment of an energy policy.

But it is crucial. It is, at least, a beginning from which larger decisions can proceed.

Passage of the bill would be reassurance to this country's friends abroad that Congress is coming to grips with a subject that American tradition and political parties make perculiarly difficult. It would be evidence that the United States means to carry out its pledges. Defeat of the bill would convey the opposite message. The choice, as the Senate now confronts it, is between doing something and doing nothing.