In the Dune universe, when a laser weapons hits a shield, both are destroyed in a nuclear explosion reaction.
So instead of building nuclear weapons, wouldn’t it be easier to tie a timer and a “parachute” to a laser gun and drop it from orbit onto your enemy’s city?
I’m not entirely sure how you would rig the lasgun to fire in a way that hits the shield, while it’s falling from the sky. And I believe it’s random whether or not the shield blows up, so you’d need to drop several for safety.
But at the end of the day, deliberately engineering explosions using shield-laser interactions still contravenes the convention against atomics. The great houses all have plenty of nukes, they really don’t need bootstrap solutions. The problem is political, not technical.