the national guard of the united states is the largest of the organized federal reserve military forces in the united states. the national guard of the united states is classified (under title 10, united states code (see above)) as the organized federal reserve military force. under federal control, the national guard of the united states can be called up for active duty by the president of the united states. since the 2003 invasion of iraq, many national guard units have served overseas – under the total force policy of 1973 which effectively combined the national guard with the armed forces, making them regular troops. this can lead to problems for states that also face internal emergencies while the guard is deployed overseas. to address such issues, many of the states, such as new york and maryland also have organized state "militia" forces or state guards which are under the control of the governor of a state; however, many of these "militia" also act as a reserve for the national guard and are thus a part of it (this varies from state to state depending on individual state statutory laws). new york and ohio also have active naval militias, and a few other states have on-call or proposed ones. in 1990, the united states supreme court ruled in the case of "perpich v. department of defense" that the federal government has plenary power over the national guard, greatly reducing (to the point of nonexistence) the state government's ability to withhold consent to federal deployments and training missions of the national guard.