Alternatively, small drones exist, and so do low power devices you could slingshot/shoot into a secure area and set to auto wipe after they've done their job. Maybe could even build it out of biodegradable material so it'll clean up in short time.
replyIf you've got secret agents on enemy soil who can get near targets with drones, you're probably just bombing them.
replyUnless you're running out of munitions.
replyAnd nuclear isn't exactly a great option.