Patriots should organize when in DC. Logical fighters first line of defense, hand combat 2nd line, non lethal weapons support, followed by armed support.
Break into groups of 20. Leaders should be able to call up other groups to defend from the unruly. Elderly and children to the center and should be protected on all sides.
Have numbers of people who can give medical attention. Never turn your back on opponents. Always expect sneak attacks from all sides and flying debri. Have water and eye wash. Wear helmets and any protective gear.
Having a flag pole to raise and then flip upside down could be a signal for distress that others in the crowd can address. Never go alone. Never stand within 4 feet so you have time to react. Always use a stop hand pointed towards the throat to back off people who want to get into your space. You are up against sneeks, never forget that. While you argue, the next blind sides you. They will kick you while down.
Never give them an opportunity to blind side the strength that you have. If you watch antifa fight, they like to divert attention before another blind sides you. A great way to lose a weapon to the enemy.
It would be nice also to have transportation there. A few vehicles that if someone gets hurt that they can be quickly moved. Antifa likes to block traffic so plan on that.
Communication is an essential. Don't plan on them being nice. If they beat you down, you may never be the same. And don't leave anyone straggling, when you leave you all leave.
Patriots, please consider up till now the only antifa that has fought are children living in their mother's basement. There is a good chance that they will bring hardened ISIS/Antifa fighters from the middle east into the mix. This is their last stand. I fought one of those people, they are trained in krag magrav and MMA and know how to fight with objects. Be aware.