Remember: Technically, the president doesn't have the power, on social media or otherwise, to formally declare war.
On September 25, North Korea accused US President Donald Trump of declaring war on the communist state.
Pyongyang's accusation, coupled with a threat to shoot down American warplanes flying near North Korean airspace, came six days after Trump addressed the United Nations General Assembly in New York City. In his remarks, Trump warned America could "totally destroy" North Korea in order to stop that country's expanding nuclear weapons program.
"The whole world should clearly remember it was the US who first declared war on our country," Ri Yong-ho, North Korea's foreign minister, told reporters in response to a September 23 tweet from Trump. The tweet, which calls out Ri and refers to North Korean dictator Kim Jong-un as "Rocket Man," amounts to a "declaration of war," Ri added.
In fact, Trump doesn't have the power to formally declare war. Only Congress does. And the US hasn't officially declared war since World War II, instead relying on UN resolutions and vague, open-ended Congressional authorizations of military force to legally justify what is obviously war.
Besides, the US is already in a legal state of war with North Korea—and has been since 1950, the year the UN endorsed international intervention in what would become the Korean War.
The Korean War never actually ended, legally speaking. In July 1953, the combatant countries—the United States and its allies on one side, North Korea and China on the other—agreed to an armistice halting active fighting, but without actually settling the conflict.
"Since there is only an armistice, the US and North Korea—or, more accurately, UN forces and North Korea—are still in a state of armed conflict or war," James Kraska, a Harvard law professor and expert in the legal aspects of armed conflict, told Motherboard.
Of course, all this legal and rhetorical sparring means little in practical terms.
The armistice isn't the only reason Trump's threat to "totally destroy" North Korea doesn't represent any kind of legal war-declaration. Pyongyang's argument simply wouldn't hold up in court, proverbially speaking. "There is no legal case by North Korea," Kraska said. "If anything, it is the other way around."
That's because the UN charter, to which Pyongyang is a signatory, forbids aggressive force or threats of war, Kraska explained. And Pyongyang, not Washington, initiated those threats a long time ago.
In recent years, Kim Jong-un has repeatedly ordered his military to launch unarmed ballistic missiles toward Japan, where the US possesses several large bases. "North Korea has made explicit threats against the United States for decades, and these do constitute a violation of the charter," Kraska said.
Of course, all this legal and rhetorical sparring means little in practical terms. North Korea doesn't need legal cover for its ongoing nuclear and ballistic-missile tests. It can act unilaterally, and count on its small-but-growing atomic arsenal to deter meaningful military retaliation by America or any other country.
Likewise, the US can exert its own military force, deploying ground troops, warplanes, and warships on and around the Korean Peninsula, in the hope of creating a deterrent effect and curtailing, if not halting, North Korea's nuclear efforts.
And then there are America's own nukes, of which there are thousands. They, more than any formal declaration of war, are what prevent North Korea from translating military threats into military action.
But even if Trump's recent remarks are not in fact a declaration of war, does his tweet at least violate Twitter's guidelines?
"You may not make threats of violence or promote violence, including threatening or promoting terrorism," according to the "abusive behavior" section of Twitter's rules. "Any accounts and related accounts engaging in the activities specified below may be temporarily locked and/or subject to permanent suspension."
As the company explained in a blog post, Trump's tweets haven't been taken down because their "newsworthiness" is of value to the "public interest."
Twitter did not immediately respond to a request for comment.
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