Controversial? Absolute horse****.
The UK has been able and willing to inflict nuclear retribution on its enemies for the last 60 years or so. The U.S. actually did!
I fail to see the difference between firebombing an enemy city and nuking it, in terms of civilian casualties.
If you don't want that to happen, then play nicely at the outset, or the big boys will come and kick your arse right out of the playground.