He is. CPT Khan died as a US citizen in the service of his country. He was killed by Radical Muslim Terrorism and US policies which have been at fault for its spread. These are policies which hillary made even worse.
Khan doesn’t seem at all concerned about the radical ISLAMIC jihadists who actually killed his son, or the vast numbers of jihadists who are slaughtering people all over the world.
No, Khan is only concerned with maximizing the flow of Muslim immigrants into the USA and with stopping Trump from stopping this process.