[zabzonk]

The USA never even declared the Vietnam "conflict" as a war, or Korea, come to that, though that did at least have the backing of the UN.

[riffraff]

It's not just the US, very few wars have been formally declared after WW2, because we all learned war is bad™, so we added more and more rules (both international and national) to make it harder to do it.

But the reasons wars existed didn't go away, so this just resulted in more and more people getting killed in "special military operations" or similar things. See e.g. "Why States No Longer Declare War"[0].

[0] https://www.researchgate.net/publication/228896825_Why_State...

[adrian_b]

That article says that nowadays countries no longer declare war, because now there are a lot of international treaties that restrict what may be done during wars.

Not declaring war provides a workaround, allowing the states to do whatever they desire, without constraints, while avoiding being accused that they do not observe their obligations assumed internationally.

Seems plausible.

[consp]

As soon a country agrees to enter a conflict on a side, which the original axes declare to be a war, it's at war. You can tell the media whatever you want of course.

[gpt5]

The US didn’t declare war since WW2 because such a declaration would give the president disruptive powers (such as the power to seize factories).

In fact, after Vietnam war congress specifically created a law to restrict hostilities without congress approval to up to 60 days, which is what the current (and prior) administrations are acting on.