It's an ugly dispute between old friends who share an undefended border and a free-trade agreement, launched by a pro-business leader known for his pugnacious style and his distaste for anything he considers to be socialism.
Wait. You thought we were talking about Canada, the United States and President Donald Trump? Sorry. Not this time.
This dispute is set in Saskatchewan and is the handiwork of Premier Brad Wall. He announced last week that vehicles with Alberta licence plates would be banned from new provincial government road and infrastructure projects. The move forces Alberta companies that successfully bid on Saskatchewan government contracts to register their vehicles in Mr. Wall's province.
The Premier says he is retaliating against a move by the Alberta government to keep Saskatchewan companies from bidding on projects in that province, although he has provided little evidence of that happening. He also says Alberta is subsidizing its craft-beer industry at the expense of brewers elsewhere.
Mr. Wall announced earlier this year that he will retire in January, after the Saskatchewan Party elects a new leader. The dust-up he has started will be remembered, badly, as his last act in office.
He insists that he is "a strong supporter of free trade." But strong supporters of free trade don't unilaterally start unnecessary spats that catch their partners off-guard, as Mr. Wall appears to have done.
Alberta's NDP government says Mr. Wall made no effort to contact it before launching his retaliatory strike. Alberta has responded by filing a complaint under the New West Partnership, the free-trade agreement that governs the four western provinces.
This is all so petty. Canada as a whole needs to eliminate provincial trade barriers that can make it more difficult for Canadian companies to do business in this country than in a foreign one. The sight of a premier grandstanding over relatively minor disputes is a reminder of the truism that short-sighted populists are the biggest barriers to free trade.