Daily Chinese Idiom Guessing Game
Describes a situation that is on the verge of exploding or breaking out; imminent danger or tension.
触碰；即就。原指把箭扣在弦上，拉开弓等着射出去。比喻事态发展到了十分紧张的阶段，稍一触动就立即会爆发。
毛泽东《评蒋介石发言人的谈话》共产党主张成立联合政府，就为罅内战。现在蒋介石拒绝了这个主张，致使内战有一触即发之势。”
The tension between the two countries was like a powder keg ready to explode at any moment - a situation of '一触即发'.