declare war against

declare war against (someone or something)

1. To officially announce the intention to fight against an enemy country or group in a war. We will have to declare war against the rebels if they advance over our border.
2. To announce the intention to vehemently oppose someone or something. This usage does not refer to physical fighting. The mayor has declared war on crime in our city and is bolstering our police force.
See also: declare, war
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

declare war against someone or something

 and declare war on someone or something 
1. Lit. to formally announce that one will fight a war with someone or some country. A group of countries declared war against the aggressor.
2. . Fig. to announce a serious campaign against a type of person or a serious problem. The president declared war against crime and criminals. The pressure group declared war on waste.
See also: declare, war
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in classic literature ?
No international difficulty ever arise to enable us to declare war against some transatlantic power?
Nor did he know how even to the last John Carter, Warlord of Mars, had refused to permit the jeddak of Helium to declare war against either Ptarth or Kaol, because of his implicit belief in his son, and that eventually all would be satisfactorily explained.
The queen pressed her brother and the Emperor of Austria to appear to be wounded, as they really were, by the policy of Richelieu--the eternal object of which was the abasement of the house of Austria--to declare war against France, and as a condition of peace, to insist upon the dismissal of the cardinal; but as to love, there was not a single word about it in all the letter.
' The site is where freedom fighters assembled from the forest on July 6, 1952, to declare war against the colonial administration, its loyalists and agents.
The President made this speech in Leyte, where he slammed the US for treating the Philippines as a "bait" and for "egging us." In my book, such a speech was totally unnecessary for the simple reason that the US would never declare war against China.
Sison's reported remark came after Duterte's challenge to the US to declare war against China over the latter's continued militarization in the disputed West Philippine Sea.
The US released a video showing supposedly Iranian boats putting on the magnetic mines in order to create a wave of anger against Iran and to urge Japanese President to declare war against Iran.
We'll declare war against them, we can beat them," he stated.
Defense Secretary Delfin Lorenzana does not believe that President Duterte would declare war against Canada over the tons of garbage that were shipped to the Philippines in 2013.
The easy tip of winning Indian election is to declare war against Pakistan, the PPP senator said adding that the neighbouring country was using war obsession as electioneering.
Senator further added that the easy tip of winning Indian election is to declare war against Pakistan and adding that the neighboring country was using war obsession as electioneering.
The BNC suggested that the Prime Minister Narendra Modi-led BJP government should declare war against Pakistan, as Islamabad declared proxy war against New Delhi by carrying out terror activities.
President Rodrigo Duterte has threatened to declare war against China if it monopolises oil and uranium resources in the West Philippine Sea (South China Sea).
1914 - Germany and Russia declare war against each other during First World War.
If passed, it would force Trump to either declare war against Yemen or end U.S.