The president said he had identified funds even though Congress has not appropriated new money for the military.

© Michael A. McCoy for The New York Times

John Ismay, who reports on the Pentagon for The New York Times, describes what National Guard troops and civilian law enforcement are doing in cities where President Trump has mobilized them.

Mining materials to make cement, gravel and a host of other common products require an explosive that is becoming more expensive and limited in supply.