I'll explain it.
It's different because people on the right were calling for people to be doxxed for things that literally every sane person in the world agrees with - i.e. murdering people based on their beliefs is something that should not be tolerated. So yeah, let's dox those people in order to shame them and root out what is a sick and anti-social sect of people who for whatever reason seem to be gaining power in our country.
On the other hand, people on the left were using doxxing as a means to impose a measure of social pressure and control on groups of people they would fear would speak out against their latest social fad / cause: all whites are racists, but Blacks cannot be racist; transgenderism is natural, etc, etc. In other words they're using doxxing to avoid having a conversation about what are controversial topics.
In short, the right is using doxxing to preserve society and social norms. The left is using it to undermine society. See the difference? I will say fairly, that using doxxing to target bystanders (i.e. someone's family) is gross no matter what the circumstances. Sins of the father and all...
And I'm not sure what your opinion is on nuclear weapons, but we wouldn't respond in-kind to NK with a bio or chem attack because we don't have those types of weapons anymore. But if NK used bio / chem in an appreciable way (not a couple shells here or there) that was going to turn the tide of battle in their favor, you better believe we'd pull out the nukes.