A European ambassador happened to be in our office the afternoon Alexander Haig resigned as US secretary of state. No offense to replacement George Shultz, but the ambassador hated to see Haig go. He felt that the former NATO commander understood and appreciated European points of view. He and other Europeans must now be hoping that Washington was listening when Mr. Haig broke his silence of six weeks and spoke to the American Bar Association the other day. Haig did not express any of the disagreement with the administration that evidently caused him to resign, but he reiterated some thoughts from which US policy toward Europe could benefit.
* The European allies have been doing their share for the common defense in NATO. Mr. Haig offered figures to show that during the 1970s the US contribution to NATO declined while that of the Europeans went up. He said that , if there had been a conflict when he was commander of NATO, he would have called on Europeans for 90 percent of his ground forces, 80 percent of his naval forces, and 75 percent of his air force.
Such perspective is useful when some would advise the President to reduce US commitments to Europe, even to the point of pulling out except for the nuclear umbrella. Europe could reasonably undertake more and more of its own defense. But not at the expense of overreliance on the bomb.
Britain's weekly Economist has recently completed calculations on the quantity of extra troops and conventional equipment needed to provide non-nuclear deterrence. The results, it reports, are ''surprisingly cheerful,'' basically requiring NATO nations to spend an additional 1 to 1.5 percent a year on defense. There are many facets to be considered. But, as the Economist suggests, this modest rearmament for the sake of ''practicable denuclearization'' should become the centerpiece of the defense debate.
* America does not have the luxury of engaging in ''protective devices'' to shield its economy from foreign goods and services. It is a point to remember as the administration decides how far to respond to the clamor by industry and labor for protectionism from European and other foreign products.
* It is a myth that the United States must face increasing hostility from have-not nations in a world of declining resources. Haig was in effect echoing European concern for dealing constructively with the third world, a concern that ought to receive more attention in Washington. He described nations becoming disillusioned with the economic results of Marxism and groping toward productive relationships with the Western world. If America turns a deaf ear, he warned, it will ''reradicalize'' these developing countries.
* It is another myth that the US must choose between appeasement or confrontation with the Soviet Union. Here again the Europeans could approve Haig's words and the Reagan team continue to learn from its former member. The way confrontational politics can boomerang is illustrated in President Reagan's sanctions against the Soviet pipeline. Ironically he has come closer to confrontation with his allies than with Moscow.
* Surges between extremes must be avoided in the conduct of foreign relations. This might seem to go without saying. Yet by saying it Mr. Haig at least offered a word to the wise in an administration that has had enough swings in emphasis to bring criticism from Europeans who would like more consistency. Mr. Haig's solution is a bipartisan foreign policy, a suggestion especially worth noting in such a firmly partisan administration as the present one. It was one more thing his old NATO friends must have liked to hear.