We must declare war against this kind of idea.

我们要与这种思想作斗争。

youdao

The lack of proprieties would make the most intimate friends turn to be the most decided enemies and the friendly or allied countries declare war against each other.

缺了礼节，最亲密的朋友会变成死敌，友好或结盟的国家会兵戎相见。

youdao

A few members of Congress did not want to declare war against Mexico.

VOA: special.2009.02.26

He didn't name names and given that it is eight years since the Tories went into an election offering the option of scrapping the assembly he may have been almost the last Conservative to declare the war against devolution is over.

BBC: Sergeant Wilson, Corporal Jones and the prime minister