The USA military is not supposed to be deployed within the sovereign borders of the country. That is the job for the National Guard!
This is not an invasion of enemy troops. These are impoverished people with the majority women with children and unescorted minors. The USA military are not to be used for babysitting services. The USA military have training for combat. The people from the Northern Triad are unarmed.
The only control necessary is crowd control during processing and humanitarian aid and plenty of it. The aid has to include food, water and medical needs including vaccines for those processed with protected status to enter the USA.
Due to the hardening of the Mexican borders a man was killed. The migrants proceeded through the additional measures to stop them. Human rights groups have stated some of the measures being deployed to stop the migration were violating human rights.
The USA is the destination for these people, if met with humanitarian aid there should be a peaceful movement. We already know there are lines at the legal crossing points as processing is conducted. Migrants are not known for violence.
President Trump needs to release foreign aid funding to the Northern Triad governments as the processing returns many of the migrants with their children home.
The USA immigration system is broken. The courts are overburdened and slow. The families must stay together as this is the best outcome for the children. The unaccompanied minors have a different track for processing that is already well established, over burdened with this many migrants.
Currently the migrants are at least more than 1000 miles from the USA border. Due to the hurricane and persistent storms this segment of their journey holds great peril.