Define "effective". Can a government do anything they want when they fear the people, no. Can they legislate in progressive ways that build an economy and keep people safe, absolutely.
On a grander scope, notice how Taiwan has not been invaded by China despite their decades of rhetoric. They're armed, the price is high and the move would be risky.
And no you dont just pray at the time you need a weapon and it pops up in your hands. That's not how things logistically work. Also a big part of it is an ongoing cognitive deterrence. That doesnt happen when people dont have them at the present time.
Just like we don't use 'I brake for whales' or this old chestnut:
https://quoteinvestigator.com/2011/10/20/last-tree-cut/
As a basis for any real discussion of environmental policy.