Maybe he's a mole, a double agent working to sabotage trade liberalization efforts from within.

It wasn't long ago, after all, that Mr. Marchi, by much foot-dragging and demands for exclusions, helped to deep-six the Multilateral Agreement on Investment. Now he's threatening to do the same to NAFTA, or at least one of its signal provisions: Chapter 11, a set of rules, like the MAI, requiring fair treatment of foreign investors. Mr. Marchi claims the provision needs "clarification," and is seeking leave from the United States and Mexico to add an "interpretive note" watering down its protections.

This is, of course, nonsense. Chapter 11 is crystal clear, and rooted in familiar principles of domestic and international trade law. These are, first, "national treatment," meaning foreign investors are subjected to no more stringent regulations than apply to a country's own nationals; and second, that foreign investors are entitled to compensation when their property is expropriated, just as you would be if your house were torn down for a freeway.

Apparently, the "problem" with this provision is that some investors are actually making use of it. Not many, mind you: In the past year, there have been four cases of American investors claiming compensation from Canadian governments under Chapter 11. Two Canadian firms, meanwhile, have launched similar lawsuits in the United States. That's six in total, the basis of all those media reports on the "avalanche" of NAFTA litigation, and of Mr. Marchi's sudden interest in clarity.

But what, beyond a few bothersome headlines and a ministerial fax machine clogged with urgent messages from the Council of Canadians, is the problem here? Certainly the facts of the cases do not support the contention that corporations are exploiting a loophole in the agreement to eviscerate each country's safety and environmental laws.

Take the case of Sun Belt Water Inc. In 1990, the California company formed a joint venture with Snowcap Waters Ltd. of Vancouver to export water from British Columbia -- with the province's blessing. Later, the province decided to ban water exports, effectively confiscating a good part of the value of their investment. Is Sun Belt suing to prevent the province from regulating water use as it sees fit? No. It is suing for compensation -- the same compensation that was given to its Canadian partner.

Or consider the plight of S. D. Myers Inc., an Ohio firm that had lined up several customers to ship PCBs south of the border for treatment. The company had the misfortune to be doing business in Canada during Sheila Copps' reign at the federal Department of Environment. Ms. Copps had banned the exports of PCBs in 1995, though the transport of PCBs across Canada for the same purpose continued unimpeded, and though there was in fact "no strong environmental argument" for closing the border, as an internal memo advised the minister.

The government would appear to have conceded the justness of the company's claim: 15 months after the ban was imposed, it was revoked by Ms. Copps' replacement at Environment, one Sergio Marchi. The same applies in the celebrated case of Ethyl Corp., another victim of Ms. Copps' interventions, this time banning the gasoline additive MMT. After months of stonewalling, the government eventually struck down the ban, and agreed to pay Ethyl $13-million in compensation.

Far from an abuse of process, these appear to be legitimate complaints, asking no more than the protection from discriminatory or arbitrary treatment that NAFTA was intended to provide. Indeed, if there is any weakness in the provision, it is that domestic investors were not given the same right to compensation as foreigners.

Hmmm. Maybe that's Mr. Marchi's game: a double-double-cross, wherein he pretends to be kowtowing to the left, only to smuggle in a property rights amendment under cover of "clarification." Fiendish bugger. How could I have been so blind?