The airline industry, which had been deregulated in the 1970s with the goal of increasing competition, was allowed to merge into an increasingly smaller number of “major” airlines. Delta bought Northwestern airlines; United bought Continental, and American bought U.S. Airlines, reducing the total number of traditional major airlines to just three. Since then, the airlines have found it easy to cooperate on matters like the shrinking of seats or the introduction of new fees, yielding unprecedented profit for years on end.
The airline industry was previously unprofitable and required consolidation to be viable. "Unprecedented profit" should say "profit at all".