Iran Is Rapidly Buying Air Defenses: Can They Stop the U.S. Air Force? Iran’s military planners face an unenviable military challenge: preparing defenses against air attacks from the most formidable air forces on the planet. Here's What You Need to Remember: Massed together, Iran’s air defenses provide Tehran with a degree of deterrence because they increase the difficulty, expense and time required to launch air attacks on Iran—particularly from regional actors. They pose a threat to non-stealth fighters unless suppressed, and can deny Iranian and Persian Gulf airspace to less agile aircraft like the RQ-4N drone shot down in June 2019.