How can I do a virus scan on iPhone?

I’ve noticed the absolute lack of answers from Apple on this previously posted question, and I have seen responses stating it is nearly impossible on iOS, which is an incorrect statement, furthermore is everyone forgetting Edward Snowden and his whistleblowing concerning NSA arbitrarily monitoring all American citizens? Are we also forgetting the documents that implicate Apple, verizon, and various other companies that were forced to comply with this illegal surveillance? The point is, if the government can do it, hackers figured it out a long time ago. Why doesn’t Apple provide some kind of malware or virus scan?