Actually that's Paul Verhoeven and Edward Neumeier writing the movie Starship Troopers, which I maintain is a dumb movie with aspirations of being a smart movie, pretending to be a dumb movie.

Just as an example, in the scene where the guy asks why they're learning to throw knives when they have ICBMs, here's Heinlein's take:

Once, during one of the two-minute rest periods that were scattered sparsely through each day’s work, one of the boys — a kid named Ted Hendrick — asked, "Sergeant? I guess this knife throwing is fun... but why do we have to learn it? What possible use is it?"

"Well," answered Zim, "suppose all you have is a knife? Or maybe not even a knife? What do you do? Just say your prayers and die? Or wade in and make him buy it anyhow? Son, this is real — it’s not a checker game you can concede if you find yourself too far behind."

"But that’s just what I mean, sir. Suppose you aren’t armed at all? Or just one of these toadstickers, say? And the man you’re up against has all sorts of dangerous weapons? There’s nothing you can do about it; he’s got you licked on showdown."

Zim said almost gently, "You’ve got it all wrong, son. There’s no such thing as a ‘dangerous weapon.’ "

"Huh? Sir?"

"There are no dangerous weapons; there are only dangerous men. We’re trying to teach you to be dangerous — to the enemy. Dangerous even without a knife. Deadly as long as you still have one hand or one foot and are still alive. If you don’t know what I mean, go read ‘Horatius at the Bridge’ or ‘The Death of the Bon Homme Richard’; they’re both in the Camp library. But take the case you first mentioned; I’m you and all you have is a knife. That target behind me — the one you’ve been missing, number three — is a sentry, armed with everything but an H-bomb. You’ve got to get him... quietly, at once, and without letting him call for help." Zim turned slightly —thunk! — a knife he hadn’t even had in his hand was quivering in the center of target number three. "You see? Best to carry two knives — but get him you must, even barehanded."

"Uh — "

"Something still troubling you? Speak up. That’s what I’m here for, to answer your questions."

"Uh, yes, sir. You said the sentry didn’t have any H-bomb. But he does have an H-bomb; that’s just the point. Well, at least we have, if we’re the sentry . . . and any sentry we’re up against is likely to have them, too. I don’t mean the sentry, I mean the side he’s on."

"I understood you."

"Well... you see, sir? If we can use an H-bomb — and, as you said, it’s no checker game; it’s real, it’s war and nobody is fooling around — isn’t it sort of ridiculous to go crawling around in the weeds, throwing knives and maybe getting yourself killed... and even losing the war... when you’ve got a real weapon you can use to win? What’s the point in a whole lot of men risking their lives with obsolete weapons when one professor type can do so much more just by pushing a button?"

Zim didn’t answer at once, which wasn’t like him at all. Then he said softly, "Are you happy in the Infantry, Hendrick? You can resign, you know." Hendrick muttered something; Zim said, "Speak up!"

"I’m not itching to resign, sir. I’m going to sweat out my term."

"I see. Well, the question you asked is one that a sergeant isn’t really qualified to answer... and one that you shouldn’t ask me. You’re supposed to know the answer before you join up. Or you should. Did your school have a course in History and Moral Philosophy?"

"What? Sure — yes, sir."

"Then you’ve heard the answer. But I’ll give you my own — unofficial — views on it. If you wanted to teach a baby a lesson, would you cut its head off?"

"Why... no, sir!"

"Of course not. You’d paddle it. There can be circumstances when it’s just as foolish to hit an enemy city with an H-bomb as it would be to spank a baby with an ax. War is not violence and killing, pure and simple; war is controlled violence, for a purpose. The purpose of war is to support your government's decisions by force. The purpose is never to kill the enemy just to be killing him... but to make him do what you want him to do. Not killing... but controlled and purposeful violence. But it’s not your business or mine to decide the purpose or the control. It’s never a soldier’s business to decide when or where or how — or why — he fights; that belongs to the statesmen and the generals. The statesmen decide why and how much; the generals take it from there and tell us where and when and how. We supply the violence; other people — ‘older and wiser heads,’ as they say — supply the control. Which is as it should be. That’s the best answer I can give you. If it doesn’t satisfy you, I’ll get you a chit to go talk to the regimental commander. If he can’t convince you — then go home and be a civilian! Because in that case you will certainly never make a soldier."

...and in the movie the guy just gets a knife through the hand and Zim says "Try to push a button now!" They're not exactly equivalent. This (admittedly quite long) series discusses the issues with Verhoeven's interpretation of Heinlein, but the short of it is that Verhoeven and Heinlein were such fundamentally different people that the very idea of Verhoeven adaptating Heinlein is absurd.