U.S. stocks might face a bubble-level pullback in June AI and semiconductors have pushed U.S. stock valuations back to historic highs, but if the Iran war triggers a surge in oil prices and a rebound in inflation, U.S. Treasury yields could continue to rise, forcing the Fed to shift from dovish expectations to a hawkish stance. For tech stocks that heavily rely on future earnings and low interest rates, this could be the trigger that bursts the bubble.