How can anyone declare war on an emotion? Terror.
See below.

Terror
Terror Ter"ror, n. [L. terror, akin to terrere to frighten,
for tersere; akin to Gr. ? to flee away, dread, Skr. tras to
tremble, to be afraid, Russ. triasti to shake: cf. F.
terreur. Cf. Deter.]
1. Extreme fear; fear that agitates body and mind; violent
dread; fright.
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Terror seized the rebel host. --Milton.
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2. That which excites dread; a cause of extreme fear.
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Those enormous terrors of the Nile. --Prior.
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Rulers are not a terror to good works. --Rom. xiii.
3.
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There is no terror, Cassius, in your threats.
--Shak.
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Note: Terror is used in the formation of compounds which are
generally self-explaining: as, terror-fraught,
terror-giving, terror-smitten, terror-stricken,
terror-struck, and the like.
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Nowhere in there does it suggest that terror is a group of people, nation methodology or even ideology. What's to declare war on? It seems like almost declaring war on sadness.. The dreaded Sadnesssists!

We've declared a war on drugs.

Why do folks use drugs? To try and be happy.

Can't have that now, can we?

I agree with you...but languages evolve...disrespect is now considered a verb and other examples:)

Same way people declare war on poverty or any other political hobby horse.

The proper phrase is "War on Terrorism". and if you read a bit you will see most people use it.

Fear and terror are warred upon by the spirit of forgiveness. to look past.
I have waged war on fear itself. Anxiety is a red flag. I beat terror at a macro level as impending doom of so called conspiracy theories. No fear. If I can beat that macro fear, I can beat any micro fear. A spiritual war is the war on terror. Refuse......Resist.....terror. With forgiveness I can look past all the previous terror of humanity knowing that there is a plan for consummation.
We are ever advancing. A statement that Einstein could not comprehend. We have not lost our dead. In my opinion. No select group is going to be saved. We are all God's children. If you believe in light which is undeniable then I think it is safe to say you believe in God. What does religion have to do with that? Fear itself is the ultimate enemy. It is a corrosive thread. It breeds terror. I believe that anyone who has tasted death is ultimately humbled. Knowing now that we are NOTHING without light. The future is bright. And eternal. infinite. science says so.

The U.S will find a way and finance it with a tax on happiness. . that is whatever you have that makes you happy. Oh, we've already got that.

I think perhaps you are correct. It would probably be more grammatically correct to declare a war on "terrorism."