I have done some research on intercepting nukes. I wrote a complete research document on the issue that you can find here, including the save game used for testing. https://drive.google.com/drive/folders/133KqHFjzGz3JbTeJgE1_9IEWNFdkTULc?usp=sharing the conclusions of the document is: There is no difference between intercepting nuclear devices or thermonuclear devices. Thermonuclear devices can still kill intercepting units because of their two tile blast radius, which is bigger than the 1 tile intercept radius. Bombers and Jet bombers can be intercepted as long as 50HP or more damage has been done. Mobile SAM units and Missile Cruiser are very effective at intercepting. The only time they might fail is if the unit is very low on health or has other modifiers that lower their strength which results in not doing 50HP of damage to an incoming Bomber or Jet Bomber. Without promotions, battleships only counter missiles shot from a missile silo. Anti-Air Guns do not protect from Nuclear Submarine launched devices. EDIT: the save game for testing can be downloaded below.