SO THE COAL STRIKE has ended, at last. The United Mine Worker's membership has ratified its new contract by a rather close and reluctant vote. There are hints and murmurs from all quarters that the major issues have not been resolved, but merely postponed. You will notice that no one seems to be claiming a triumph. The one direct and predictable consequence will be a very sharp increase in miners' wages, which means higher costs of coal, which in turn means higher costs of steel, electricity and all of the things that are made with them. It is not a particularly hopeful prelude to President Carter's forthcoming campaign against inflation.

THis long strike demonstrated a series of errors of judgement and preception by just about everybody involved. It started with the original strategic mistake by the coal companies, whose conduct has not done much to alter their general reputation for crude and nearsighted labor relations. The internal chaos within the union, and the rapid erosion of its leadership's authority, led the coal industry to think that the moment had arrived to impose a massive restructuring of work rules, pay and benefits. In fact, as events rapidly showed, the industry could not have picked a worse time. The miners' bottomless suspicions of their own negotiators made it nearly impossible for the companies even to convey their proposals clearly to the union's membership. The trouble was compounded by the confusion among the miners regarding the old contract. Most of the miners thought, for example, that it guaranteed them full medical benefits. That was incorrect, but misunderstandings on that point only complicated the process of arriving at new agreements.

The Carter administration had originally hoped to stay out of the negotiations altogether. But as the winter wore on and scary forecasts of layoffs and brownouts spread, the President swung around and swept the talks into the White House. Mr. Carter tends to overestimate the impact of this kind of gesture. In this instance, there was little visible effect. Eventually the administration resorted to a Taft-Hartley injunction. That procedure was sucessful only in the limited and dubious sense that almost any alternative to its use became instantly more attractive. The negotiators, on their own, promptly went back to work - while the miners were refusing to do so - and eventually produced the present agreement. But a distinctly unfortunate precedent has been set here, for the injunction has been hanging in limbo for more than two weeks - unenforced, unenforceable and ignored. In the end, both sides were pushed to agreement by the fear that, otherwise, companies and miners' locals would begin to settle separately, at great cost to both the industry and the UMW.

President Carter's energy message a year ago emphasized extremely rapid increases in coal production. The companies with underground mines in Appalachia - where the UMW is strongest - have been anxious above all to get a contract that would cut down the epidemics of wildcat strikes and absenteeism that have increasingly disrupted their operations. Whether things will improve under the new contract is very much open to question.

The startling thing about the strike, as it wore on, was the minimal disruption that it caused. By the end of the strike, according to government figures, coal burning utilities were getting 77 per cent of normal deliveries and most big industrial users were actually accumulating stocks. This coal is coming mainly from strip mines, where labor is represented by other unions or none at all. The forces on which the country traditionally depends for rapid resolution of major strikes did not prove very effective: informed self-interest among both labor and management, political intervention, court action. But the effects of the strike were greatly mitigated by an unexpected flexibility in energy supply. That is probably the most significant lesson of this affair: the value of an energy system that is not crucially dependent on any single source of supply.