Not sure how this is news

>>Son, 23, who allegedly operated the site, has been indicted in U.S. District Court in the District of Columbia on nine counts of conspiracy, producing, advertising and distributing child pornography and money laundering. The government has also moved to seize 24 bitcoin accounts in a civil forfeiture proceeding.

I'm not going to search for this document but it sounds like he had customers in the US - so, boom, you just broke US law. How is this any different from someone doing something illegal with people in any other country, whether they set foot on its soil or not, and whether they're a citizen of that country or not, getting caught, and getting indicted in that country? E.g. you sell and mail drugs to France, you get caught by French customs, you're getting indicted in France. They don't care if you're a French citizen or ever set foot on French soil.

Plus this guy broke South Korean law as well.

That being said, the US' extraterritoriality and punishment of its citizens that break US law abroad is 100% bullshit.