Even if you were right what Trump currently wants is irrelevant, he's shown time and again that his positions change on a dime. Nobody truly knows what the man will do if he actually reaches office, and that's the scariest part.
+1. Trump pledges time and time again he's going to make the military great again by listening to the generals. He'll find that its quite difficult to clean up wasteful Pentagon spending when the corrupt US generals who are mostly speaking heads for the DoD and Military-Industrial Complex keep asking for money to go and build the next weapon or fight another war. If you [Жұқтыру] actually trust what Donald Trump is saying on military intervention, then he's succeeded in fooling you. That's his best quality remember. He's a con man and political opportunist.
You can say the same about all these candidates. You don't know what they're going to do. You think these candidates stick to their ideologies since they're principled? No, they stick to what is best for them and their sponsors, and also sometimes other things if they're low on public support/was a big point in their campaign and they'd look awful if they didn't do it.
Trump flip-flopping is not an argument against Trump, it's a counterargument against the argument that Trump is (decently) constant in his stances (which is rarely argued, anyway). Cruz, Kasich and whoever else can just be good at hiding what they really want to do. Being a small politician doesn't mean you'll be the same as a big politician.
I'm assuming each politician will tell the truth about what they do, which is an assumption and may not happen, but there are no guesses otherwise. And I'd pick Trump, who says he is not going to grow the military forces out, over Cruz, who says he will.