American Secretary of Defense James Mattis visited the headquarters of NATO’s Operation Resolute Support in the Afghan capital on Monday, and took the opportunity to reaffirm American support in the fight against terrorist organizations like ISIS and the Taliban who were responsible for an attack that claimed the lives of over a hundred Afghan soldiers during their evening prayer.

Mattis was accompanied by Army General John W. Nicholson, commander of the Resolute Support mission as well as all U.S. forces in Afghanistan.

“As if we needed a reminder of the type of enemy we’re up against, the killing of Afghan citizens and soldiers — protectors of the people — just as they were coming out of a mosque, a house of worship, it certainly characterizes this fight for exactly what it is,” Mattis said to the international group of soldiers.

“These people have no religious foundation. They are not devout anything, and it shows why we stand with the people of this country against such heinous acts perpetrated by this barbaric enemy and what they do.”