It's true that Donald Trump has no experience dealing with national security issues. (Neither did Bill Clinton circa 1992, by the way.) It's also true that sometimes people's extensive experience working in a certain discipline, which they hope will prove them qualified for a promotion, actually proves the opposite.
Apparently Hillary is set to give a major national security speech tomorrow in California, in advance of the June 7 primary that she may well lose as part of the march to her inevitability. And her point in this speech will be that Trump is unqualified for the presidency because of his complete lack of knowledge or preparation in the field of national security, whereas she, don't you know, has been in the arena: