Though I’m sure a rainbow flag tattoo would be perfectly acceptable given the nature of the current regime.
Several years ago, a southern state capitol came under condemnation for flying the confederate flag. THe vigorous objection was from black citizens who felt the flying of the confederate flag was racist. I listened to the uproar and came to the conclusion that the confederate flag should not be flown on the capitol because the confedracy lost and I see no point in memorializing a prior deep division. I think racism is in the eye of beholder - some may have valid reasons for finding it racist as it was the symbol of the side objection most visibly to freeing the slaves. Others simply see it as a feature of the right of states to decide for themselves regardless or even in spite of the issue of slavery etc. - not a position I support personally but I know it is out there among traditionalists. If the marines dictate that a tatoo cannot show - well that makes sense as some recruits would see it as tolerating racism and others might see it as an issue of free speech.