The Republican Party’s leading presidential contenders on Friday promised conservative activists they would pursue aggressive military action to prevent the spread of global terrorism, including a renewed use of ground forces in the Middle East. As war-weary critics in both parties watched with skepticism, one Republican White House prospect after another attacked President Barack Obama’s foreign policy as far too timid as they courted thousands of conservative activists gathered in suburban Washington. “Our position needs to be to re-engage with a strong military and a strong presence,” former Florida Gov. Jeb Bush told the Conservative Political Action Conference. Bush added he liked the option of sending ground forces into the fight against the Islamic State group, particularly to conduct intelligence and special operations. “As we pull back, voids are filled,” Bush said.