By treating wounded fighters? There's an obligation under the Geneva Convention to treat wounded fighters if they come to you or if you capture them on the battlefield.
Technically there was no obligation to help ISIS fighters. They weren’t a recognized nation or uniformed force. Thusly their fighters wouldn’t have been covered by the Geneva Suggestion in the first place.
By treating wounded fighters? There's an obligation under the Geneva Convention to treat wounded fighters if they come to you or if you capture them on the battlefield.
Technically there was no obligation to help ISIS fighters. They weren’t a recognized nation or uniformed force. Thusly their fighters wouldn’t have been covered by the Geneva Suggestion in the first place.