Preemptive strikes are okay when you know for sure what you're preempting.

当你确信你所占的先机，先发制人未尝不可。

youdao

Marketers tend to launch ambush campaigns only once an event has started, making preemptive strikes almost impossible.

市场营销员往往只要赛事一开始就开展“伏击活动”，这使得提前制止它成为几乎不可能的事情。

youdao

It has made similar statements for years threatening preemptive strikes, but those have almost always been in response to joint South Korean-U. S. military drills.

多年来它发表过威胁先发制人打击的类似声明，但是这些几乎总是对于韩美联合军事演习的回应。

youdao

The President of the United States even has the authority to green-light preemptive strikes against a credible, impending cyber-attack, according to the NYT article.

FORBES: President Obama's New Preemptive Strike Powers Target Cyber-Attackers