Before you absolve yourself of all critical thought and say "Just following orders," or "Just enforcing the law," ask yourself, who benefits from violence resulting from forced disarmament.
You? No, not if your family ends up mourning you.
Your pension? No, governments all over the world are robbing public and private pension funds to pay off debt.
Your family? See above.
Who does then?
The progressives who dream of a world where everyone remotely associated with capitalism, masculinity (that includes you cops and soldiers), religion (that includes you left-leaning religionists) and self interest are destroyed. They do not have the courage or numbers to accomplish their goal, but they can count on fanning an "us versus them" mentality, which is working so far.
The Sturm Abtielung enforced Nazi law, until they were destroyed by the Shultz Staffel.