Contrary to popular belief, the Act does not prohibit members of the Army from exercising state law enforcement, police, or peace officer powers that maintain "law and order"; it simply requires that any authority to do so must exist with the United States Constitution or Act of Congress. In this way, most use of the Army and the Air Force at the direction of the President does not offend the statute, even though it may be problematic for political reasons.
The statute only addresses the US Army and, since 1956, the US Air Force. It does not refer to, and thus does not restrict or apply to, the National Guard under state authority from acting in a law enforcement capacity within its home state or in an adjacent state if invited by that state's governor (in its federal capacity, the National Guard forms part of the Army or Air Force of the United States). The Navy and Marine Corps are prohibited by a Department of Defense directive (self-regulation), but not by the Act itself. Although it is a military force, the U.S. Coast Guard, which now operates under the Department of Homeland Security, is also not covered by the Posse Comitatus Act, primarily because the Coast Guard has both a maritime law enforcement mission and a federal regulatory agency mission.>/i>
18 USC § 1385 - Use of Army and Air Force as posse comitatus
Whoever, except in cases and under circumstances expressly authorized by the Constitution or Act of Congress, willfully uses any part of the Army or the Air Force as a posse comitatus or otherwise to execute the laws shall be fined under this title or imprisoned not more than two years, or both.
So? Have you read what all the Constitution allows military use for? Suppressing insurrection and enforcing laws are mentioned. Further, Art 4 Sec 4, could allow for any military commander to start military maneuvers in AZ/TX/NM/CA today, the Constitution affirms that the States shall be protected from invasion and those states are being invaded -- that in itself does not qualify as posse cometaus, but what if they besieged sanctuary cities, cutting them off from water and power until they turn over the traitors instituting such policy?