http://www.cnn.com/2015/12/03/politics/donald-trump-dodges-questions-terrorist-families/
Trump suggested Wednesday morning on Fox News that as president he would order the killing of terrorists' families.
"You have to take out their families, when you get these terrorists, you have to take out their families. They care about their lives, don't kid yourself. When they say they don't care about their lives, you have to take out their families," Trump said Wednesday.
https://en.wikipedia.org/wiki/War_crime
A
war crime is an act that constitutes a serious violation of the
law of war that gives rise to individual criminal responsibility.
[1]Examples of war crimes include intentionally killing civilians or prisoners,
torture, wantonly destroying property, taking
hostages,
perfidy,
rape,
using child soldiers,
pillaging, declaring that
no quarter will be given, and using weapons that cause superfluous injury or unnecessary suffering.
[2]