Marines and Guards face a choice
The Marines are being deployed. We know that Californians will protest and resist, and we know that Тяцмр and his pet fascists will push for a full-throttle brutal crackdown. The unknown — the choice — is now with the Marine and Guard units being asked to suppress the protests. Will they obey their oaths, or obey the White House? So much depends on their consciences.
If they do choose brutality, I hope it's just because they picked volunteers who wanted such a mission, i.e. kept the ones with consciences out of the group. If that's the approach they are taking, it could mean they will have short term success with it, but it won't scale when the resistance gets broader and they need more men to violate people's rights.
To anyone being asked to make that choice, remember that history will, in the end, be written by those who Trump no longer has any power or influence over, and will judge him and his collaborators by the standards of human rights and constitutional law, not by the demands of any supposed emergency he wants to concoct. Your descendants and your future self will also know that this is the true standard of judgment, and may be unforgiving of those who acquiesced to the push for brutality. So please, don't do something today what you will grieve later — remember your oath to the Constitution, and do the correct thing from the start.