Infringe means to restrict in ANY way. They didn't say PROHIBIT. They said INFRINGE. And the framers of the Constitution were highly literate men who wrote with extreme precision and clarity. So, there should be no restrictions whatsoever on the right of the people to keep military arms. Even the licensing and tax requirement for fully automatic weapons would have been judged non compliant with the Second Amendment by George Mason the primary author of the amendment.