The U.S. State Department announced new sanctions against North Korea on Tuesday that are directly tied to the February 2017 murder of Kim Jong-nam, the half-brother of dictator Kim Jong-un.

The State Department referenced a finding reached a few weeks ago under the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991 that Kim Jong-nam was killed with VX chemical warfare agent at the airport in Kuala Lumpur, on the orders of the regime in Pyongyang.

“The United States strongly condemns the use of chemical weapons to conduct an assassination. This public display of contempt for universal norms against chemical weapons use further demonstrates the reckless nature of North Korea and underscores that we cannot afford to tolerate a North Korean WMD program of any kind,” the State Department said.

“It’s unclear why the U.S. State Department chose to make the announcement Tuesday, hours after South Korea said the Kim regime would be willing to speak with the U.S. about giving up its nuclear weapons,” CNN remarked on Wednesday, finding the new action largely symbolic because the sanctions going into effect on March 5 largely overlap with earlier measures taken against North Korea’s nuclear missile program.

Reuters likewise sees the sanctions as symbolic and finds them curious when juxtaposed against President Donald Trump remarking that he believes the North Koreans are “sincere” about negotiating for denuclearization, although he added their sincerity was inspired by international sanctions and “the great help that we’ve been given from China.”

Of course, one purpose for the new sanctions could be sending Pyongyang an unmistakable signal that its Winter Olympics “charm offensive” failed to trick anyone (outside the U.S. media establishment, anyway) into forgetting just what kind of regime they are dealing with.

North Korea appears to be getting the message, judging by a fiery editorial published by its state-run media on Wednesday:

Additional sanctions by the Trump group are nothing but last-ditch efforts to try to retrieve its continued defeats in the showdown with the DPRK. If the U.S. and its vassal forces try to suffocate the DPRK while calling for “sea blockade” and “cutting off financing line”, that will incur strong countermeasures. It is necessary for the Trump group to ponder over the fact that stronger counteraction will follow their violent acts and the misfortune will befall the U.S., not the world. Unreasonable acts will make the U.S. find itself in the miserable position.

“DPRK” is North Korea’s name for itself. “Vassal forces” is one of North Korea’s many colorful names for South Korea.

Another North Korean media outlet fumed that America is the “sworn enemy common to humankind” because of its “invariable aggressive ambition and nuclear war moves aimed at putting the world under its domination by force.”

Speaking of South Korea, its President Moon Jae-in advised leaders of his party to curb their enthusiasm for denuclearization talks, and he probably had not even read the latest spittle-flecked editorials from Pyongyang yet. He was, however, probably mindful of his own country’s media dividing itself between cautious optimism and skepticism deep enough to include allusions to Neville Chamberlain and Adolf Hitler working out “peace in our time” right before World War II kicked off.

“We are only at the starting line and it’s too early to be optimistic,” President Moon said on Wednesday.

He added that, contrary to rumor, there are no behind-the-scenes negotiations in progress with North Korea, and promised that whatever talks may occur, “There will be no such thing as a gift to the North.”

The women who applied deadly nerve agents to Kim Jong-nam’s face are currently on trial for murder and might face the death penalty. They claim they were tricked by North Korean agents who told them they were pulling a harmless prank on a random victim for a reality TV show.

In an interesting bit of recent testimony one of the women, Siti Aisyah of Indonesia, said she was employed to perform many such pranks before her fateful encounter with Kim, and indicated the North Koreans who set her up offered to fly her to Macau a week before she finally ended up going there—which would have been about two days after Kim Jong-nam arrived in the country. The implication is that Kim’s death was commissioned and planned for weeks before the hit was finally carried out, and the assassination was postponed at least once for reasons unknown.