Maybe, the Trump administration was a little to fast and loose in this case!
Caveat: I am not familiar with the details of the case nor the court order.
"The unsigned [court] order stated the government “failed to identify a source of authority that would allow the military to execute the laws in Illinois.”"
"... At this preliminary stage, the Government has failed to identify a source of authority that would allow the military to execute the laws in Illinois. The President has not invoked a statute that provides an exception to the Posse Comitatus Act. Instead, he relies on inherent constitutional authority that, according to the Government, allows him to use the military to protect federal personnel and property. ..."
