As US troops sail to Middle East, how likely is Trump to order boots on the ground?

Secretary of state Marco Rubio repeats administration's belief that US can achieve its aims without a ground war

Amid tentative White House efforts at diplomacy to end the war in Iran, US troops have also been arriving in the region to deliver what Donald Trump has hoped could be a knockout blow if he can't negotiate a ceasefire with Tehran.

Thousands of US marines aboard navy amphibious ships from the 31st and 11th expeditionary units have been deployed to the Middle East from Asia. Another 2,000-odd paratroopers from the 82nd Airborne are also being sent to the theatre - they are tasked with deploying worldwide within 18 hours of notification and execute parachute assaults, including against a defended airfield" to prepare for further ground operations.