1) It violates the "Posse Comitatus" Act, that of allowing a standing army to operate and quarter itself domestically to train for likely scenarios where it will have to be used against the LEGAL citizens of the United States of America
2) It allows an already proven tyrannical and outlaw "President" to station FOREIGN troops on DOMESTIC SOIL, troops usually considered our ENEMY, for the already stated purpose of gathering intelligence and training to be used against a "foreseeable insurrection or domestic threat" or as a tool in a "gun grab"
THIS MILITARE EXERCISE is a blatant violation of the 2nd Amendment of the US CONSTITUTION and violates the trust of WE THE PEOPLE.