Considering it's a back the blue flag, I'm going to guess they're making commentary on modern white supremacists. Neonazi openly flew the nazi flag in the 80s and 90s, then when that became too niche they moved to the confederate battleflag so they could dogwhistle a bit, then moved to back the blue once the dog whistle became too obvious amongst the general population (as if it's fooling anyone anyway)