You can lower costs by a lot dropping some requirements like component deratings, screening, temperature of operation, mean time between failures rate, etc.

You end up with a _just as good_ device that will fail way more times than before (1:100 or more instead of 1:100000) but is way cheaper and way easier to procure. When it fails just launch another.

I wouldn't specifically do this to the tomahawk as it's used in missions where accuracy is critical in order to avoid collateral damage. But otherwise I'm a strong proponent of applying "new space" logic to military gear.