George Shultz was tactful in making Canada the first country for an official visit in his capacity as US secretary of state. Canadians are often taken for granted south of the border. They should not have to rescue US hostages in Iran to be reminded of the regard in which they are held by their nearest allies.
Relations have been unnecessarily edgy lately. One reason is Ottawa's ''Canadianization'' effort to reduce US domination of business in Canada. Another is Washington's ''dream-like lack of urgency'' on acid rain, as a Canadian legislator called it during a public debate with a US legislator at the very time of the Shultz visit.
Now the diplomatic atmosphere has been improved. And so may the environmental atmosphere be improved in the wake of Secretary Shultz's agreement with Canadian External Affairs Minister Allan MacEachen to share the cost and results of more research on acid rain. As it is, Canadians charge that pollutants from US industry are damaging their lakes and forests.
Enough has long been known about acid rain for the Council on Environmental Quality to have recognized it several years ago as one of the two most serious global environmental problems linked to fossil fuel burning. (The other is the accumulation of carbon dioxide in the atmosphere.) More information on precise causes and effects is necessary for devising full and effective safeguards.
However, the extra study must not become an excuse for inaction. The Reagan administration's increase in funding for research has been accompanied with moves that have concerned environmental groups. Sulfur dioxide from coal-burning plants, for example, is seen as an ingredient in acid rain. But instead of reducing authorized emissions from existing sources the administration has increased them by 1.5 million tons a year. It has also sought legislative extensions of deadlines for satisfying sulfur dioxide standards.
The research agreed to by Messrs. Shultz and MacEachen ought to get rid of any dream-like lack of urgency and clarify just what should be done.
If acid rain has been the most publicized recent US-Canadian issue, the question of equitable economic relations is no less important for two countries whose trade amounted to $92 billion last year. Here the prospects also should be brightened as the two officials follow through on their commitments to meet regularly in the future to avoid misunderstandings.
They found ready agreement against the rise of protectionist trade policies. This was particularly welcome on the eve of next month's GATT talks in Geneva, to be chaired by Mr. MacEachen.
Mr. Shultz gave similarly welcome assurances of Reagan administration opposition to specific US legislative proposals to limit the access of Canadian lumber, trucking, and uranium to US markets. The drive to restrict uranium imports at the moment seems especially short-sighted. With plenty of uranium available from various sources, restriction would only raise prices for US buyers.
In brief, Mr. Shultz's journey northward may indicate a useful realization that, by and large, what is good for one of these good neighbors is good for the other.