AS A BRILLIANT EXAMPLE of the politics of special interests, the negotiations over the coming foreign trade bill deserve your attention. Some of the special interests are, after all, your own. Are you planning to buy a car next year, or a pair of running shoes? A ton of cold-rolled steel, or a sack of sugar? They and a thousand more items will be touched by the complex game now getting under way.

The Carter administration is negotiating a new set of world trade rules simultaneously at Geneva and at the U.S. Capitol. At Geneva, it is bringing to a conclusion more than four laborious years of bargaining with 97 other countries. The result will be the trade bill that goes this spring to Congress. Congress will, in effect, be legislating for the entire world; the new rules go into effect if Congress passes them and not otherwise. In preparation, the administration is already haggling vigorously with the people in Congress who speak for industries threatened by foreign competition.

In previous trade negotiations over the years since World War II, tariffs have been worked down to a point at which, in most categories of goods, they are hardly significant. The Geneva talks have been mainly devoted to another kind of barrier. The most important of the forthcoming agreements will be the code on export subsidies. If a government provides financing for steel exports, for example, how much generosity is permissible? There will be codes on regulation: What is a legitimate standard for auto emissions, and what is merely an attempt to protect a domestic auto industry from different but equally effective foreign technology? Is the safety-inspection procedure for television sets a necessary protection for the consumer, or is it deliberate harassment of the importer?

Persuading Congress to accept legislation of such breadth is not going to be easy. The administration's chief trade negotiator, Robert S. Strauss, is now attempting to anticipate the loudest shrieks of protest, and to placate the perennial shriekers. The triggerpricing system that restrains steel imports is going to stay in effect for a while, even though it is extremely inflationary. The administration judges, no doubt correctly, that trigger pricing is doing on the whole less harm than the import quotas that the steel industry would otherwise get from its friends in Congress.

Another commodity under pressure from abroad is sugar, and earlier this month the Agriculture Department sent Mr. Carter three options for price supports. Reluctantly, he chose the most inflationary. The chairmen of both the Senate Finance and Foreign Relations Committees come from sugar producing states. Similarly, the textile industry, with the able assistance of Sen. Ernest F. Hollings (D-S.C.), demonstrated last year that it was both willing and able to blow up the whole trade bill if its requirements were not met. A couple of weeks ago an understanding between the textile manufacturers and Mr. Strauss was trumpeted to the world; another layer of quotas will be added to the present elaborate system of textile import controls.

The latest addition to the list is the quota on imported clothespins from Taiwan and the People's Republic of China. A surge of foreign clothespins is endangering the domestic industry, President Carter found. "He expressed deep concern over the welfare of small Northeastern towns where clothespins are produced...," according to the press release from Mr. Strauss's office.

In principle, this coming trade legislation promises great benefits to the country. Expanding world trade has contributed strongly to the rising living standards here and around the world. Trade helps to keep prices down and to lift productivity. But trade is a very practical subject. The principle of free trade will be hardly worth winning if, in the meantime, the substance has been bartered off with price protection to the industry here and quota protection to another one there.