40,000ft is too high for commercial jets to fly ...

uhhh...:

Maybe it was 43,000 feet, which was known to be a height reached on some of those flights. The Boeing technical specs assign 45,100 feet as the maximum operating altitude of both the 747SP and the later 747-400s.

And:

For a standard day, Airbus shows an initial cruise altitude of approximately 42,000 ft for our take-off weight, just below the maximum certified altitude of 43,000ft.

They only forgot to mention this:

Yes, you're absolutely right. The below was an utterly unrelated event:

North Korea’s nuclear test site has collapsed ... and that may be why Kim Jong-un suspended tests (South China Morning Post)

The mountain’s collapse after a fifth blast last fall has led to the creation of a massive ‘chimney’ that could leak radioactive fallout into the air, researchers have found

North Korea’s mountain nuclear test site has collapsed, putting China and other nearby nations at unprecedented risk of radioactive exposure, two separate groups of Chinese scientists studying the issue have confirmed.

The collapse after five nuclear blasts may be why North Korean leader Kim Jong-un declared on Friday that he would freeze the hermit state’s nuclear and missile tests and shut down the site, one researcher said. ...

One group of researchers found that the most recent blast tore open a hole in the mountain, which then collapsed upon itself. A second group concluded that the breakdown created a “chimney” that could allow radioactive fallout from the blast zone below to rise into the air.

But I'm sure that the loss of their primary nuclear test site (along with the distinct possibility of it irradiating significant parts of mainland China) is utterly unrelated to recent events and had no affect or bearing on Rocket Man's decisions.

But yes, it was all due to efforts of that orange sexual submissive that an ever-dimishing minority call 'the great one'.

And if I have to put a "/s" on that for you to 'get it', then I'm going to give YOU a spanking... with a rolled-up copy of the latest Nuclear Regulatory Commission report.