sledgehammer
noun [ C ] uk/ˈsledʒˌhæm.ər/ us/ˈsledʒˌhæm.ɚ/
大锤
a large, heavy hammer with a long handle, used for breaking stones or other heavy material, or for hitting posts into the ground, etc.
（行为）过于激烈
used to describe a way of behaving that is too forceful
They accused the prime minister of using sledgehammer tactics. 他们谴责首相大动干戈。
Idiom
a sledgehammer to crack a nutidiom UK disapproving 杀鸡用牛刀；小题大做
If you use a sledgehammer to crack a nut, you use much more force than is needed.
50 police officers to arrest two unarmed men is surely using a sledgehammer to crack a nut. 出动50名警察逮捕两个手无寸铁的人，这可真是小题大做。