The inclination for arms in USA (where 'carrying guns' is a right') is not quite translational to Thailand and other countries (where 'arms' are generally prohibited). There are also 'circumstances' that determine if use of arms is not just legal but also 'justified'.

So 'use of arms can be legal' but 'use of arms MUST be justified' too.

(Polliticians often say they can do xyz because the laws allow, they forget the 'second clause' that they can only do xyz when it is justified -- ie. necessary, beneficial, appropriate, ... by 'cultural standard/norm'. Political corruption is corrution of justification!)