Tuesday, April 6, 2021 The antitrust outlook in the United States is marked by uncertainty. This article identifies some issues to watch. Some Recent Surprises Historically, U.S. antitrust enforcement has been marked more by continuity than by abrupt change. During the past few decades, we saw an evolution away from blanket rules of per se legality or illegality under federal law ( e.g., resale price maintenance and inflexible merger standards), a greater emphasis on economic analysis of likely competitive effects, and an attempt to strike a balance between overly aggressive enforcement (which inhibits potentially procompetitive conduct benefiting consumer welfare) and overly lenient enforcement (which risks adverse consumer welfare consequences).