Originally posted by Battleship_Tirpitz:

I got some ideas, though their a bit "out there."

-Maybe the AI would be more likely to join a faction with a Nuclear Power of the same ideology (Like, the UK would be more likely to join or stay in a faction with the USA if it has nukes)

-The AI's desire to actively join or start a war with a nuclear power could plummet for fear of nuclear annihilation. (Example: The UK Guarantees Finland, but the soviets declare themselves a nuclear power. Then if the Soivets justify or have a Wargoal and declare, the AI would be like 20% less likely to actually join the war against the Soviets.)

-Your Stability drops by 15% when you've been at war for over 2 years with A country as a Nuclear Power, leading to a chain of events that can lead one of 2 ways. The Population holds a vote to have you(the player) Commit to Nuclear Disarming, or You white-peace the country your fighting. (This should be a toggle option since the AI tends to get into long wars often)

-The Ability/Decision to start a "Nuclear Arms Race" with other powers, you can end it through a decision for 500 PP when you have a certain amount of Nukes compared to your enemy, although once you start an arms race, world tension increases by 0.05 every week by the nations in the race. This is based on the Cold war, where global paranoia over Nuclear War caused tensions to skyrocket.

-Once the "Nuclear Power" Spirit, Then certain nations or Ideologies (or the player) can form a Power Bloc's or Alliances with at least 4 countries of similar ideology made to counter it for either Command Power or PP. (Think Warsaw Pact v NATO)

-Nuclear states should have less time to prepare a nuclear raid.

-Another National Spirit called "Pressure from a Nuclear Power" can be added. It works similar to how the Austrian Empire Decisions and Localized Spy Training Centers work, On map decisions to add pressure to a nation for PP. 4 Types of Pressure can be included as a result.
1: Diplomatic Pressure (75 PP): The AI would be more likely to accept your demands/Join a faction with you/become your puppet, you get the gist.
2: Nuclear Pressure (75 PP, or when a Nuclear Power is justifying on you): Provides a certain amount of debuffs to the Pressured nation, like division attack, pp gain, more likely to cave to your demands/requests. but it also gives buffs like division attack on Core Territory, reduced division training time, War Support Increase if you reject the pressure, etc.
3: International Pressure (75 PP, Must have at least 3 nukes): Lets say the Soviets are at war with Japan, and the US applies diplomatic pressure to both countries, the US will have the ability to take a decision called "Forcibly Open Peace Talks in (Insert Your Country Capital)" which kicks off a series of events that can directly affect how that war ends. Using the example, You can end the war in Japans Favor, or end it in the soviets favor. Or, you can do neither and force a white peace between the two when the Leader of the Soviets get into a shouting match with Japans Leader, by taking the event option "Remind both leaders what could happen if they step out of line." you can force a white peace, but if the Aggressor nation rejects that reminder, you get a wargoal on them after one week.
Finally 4: Political Pressure (25 PP): Banking off the On map-decisions idea, the player can take a decision that can force or ask the AI or a Player to replace their leader with one that is more "Friendly" towards the player nation, Like if the US applied Political Pressure to Communist Cuba, and Cuba caved, then they would get a Leader with the trait "(Country Name) Collaborator" which buff the ideology of the country in question. Although Civil Wars can completely reverse that effect.

Welp, these are some ideas, i dont expect any of these to even get past the concept phase, but it would be pretty sweet to see at least one of these ideas added. Happy modding everyone!