You missed all the raaaaaaaageeeeeeeeeee threads about how Snap-on wasn't marking ratchets as US-made any more, so they were all made in other countries, the conspiracy theories that went along with that, the teeth-gnashing of SO loyalists trying to defend "Snap-on selling to a global marketplace where the US-made stamp simply wasn't conducive to sales" marketing blurbs, et cetera ad nauseum ad infinitum.
Non-US production is all about consistent quality control. It's possible to get good tools made in China, and moreso in Taiwan, but it takes a great effort to keep the quality consistently at the mark set by the parent company. In some cases, that simply can't be done; in other cases, it's more effective to keep production in the US. Snap-on does have non-US made tools, but in general the quality control is consistent with tight tolerances (although some of the private label stuff they simply source from other companies and slap a Blue Point sticker on isn't exactly high-quality).
Could SK move production of their tools to China or Taiwan and likely keep the quality they have now? There's a good chance it's possible, but in order to keep that quality consistent, and get the quality in the first place, wouldn't save any costs from producing the tools here in the US. And, there's the whole bit about sending money to what is essentially a financial and political enemy to the US, China.