The controversy erupting from the recent rulings of the Supreme Court of the United States (SCOTUS) on immigration policy and trade unions pushed an important decision down in the headlines. This was SCOTUS' ruling that American Express (NYSE: AXP) is not running afoul of U.S. antitrust laws by requiring merchants to abide by its "anti-steering" provisions.This is quite a win for American Express and it'll have repercussions for the broader credit card industry.