Iran has shifted its military strategy regarding U.S. forces in Iraq ahead of the U.S. presidential election in November, reducing the number of rockets launched at bases and potentially withholding its response to the January killing of its top general, according to an intelligence assessment described by U.S. officials. Some U.S. officials and analysts said Iran and its backed groups are unlikely to launch a provocative attack that could have the effect of rallying U.S. public support for President Trump in the…