In case of Iran, even without the nukes NATO will be having a hard time if they go on the offensive.
It's actually pretty funny when you learn that US regime hasn't even been able to win against Iran in their dreams

I'm talking about the biggest military exercise US had back to date called the Millennium Challenge where they spent $250 million at the time (about $400 million with today's rate) with 13,500 service members in a massive area of operation and computer simulations to accompany that.
In the first run, US was defeated in 5 minutes. ROFL
They repeated the exercise many more times each time significantly restricting the other team's (Iran) capabilities. They were miserably defeated every time.
They continued this until the commander got too angry about continues defeats that he kicked the operation table and left the whole thing.
https://www.19fortyfive.com/2022/05/how-iran-defeated-the-u-s-military-in-a-war-thankfully-it-was-a-simulation/That is from 2002 and it was not even using 1% of Iran's capabilities while used nearly the full force of US military!