Wall Street Journal:

Some operations executives suggested as early as 2015 that the company relocate assembly of at least one product to Vietnam. That would allow Apple to begin the multiyear process of training workers and creating a new cluster of component providers outside the world’s most populous nation, people familiar with the discussions said.

Senior managers rebuffed the idea. For Apple, weaning itself off China, its second-largest consumer market and the place where most of its products are assembled, has been too challenging to undertake.

And:

China has been a critical factor in Apple’s soaring market value. The country provides a stable, efficient, low-cost manufacturing base with an abundant network of suppliers that have helped cement Apple’s profitability.

And:

A clean break with China is impossible. Apple relies on a workforce of more than three million indirect workers in China. Its top manufacturer, Taiwan’s Foxconn Technology Group, hires hundreds of thousands of seasonal employees in China, many of whom manually insert tiny screws and thin printed circuit boards during the iPhone assembly process, people familiar with the process said. Tens of thousands of experienced manufacturing engineers oversee the process.

China has built a massive manufacturing machine. Massive. Moving elsewhere, starting from scratch, would be painful at the very least. It would also take time. And then there’s the availability of the raw materials, not to mention one of the world’s largest marketplaces.

It’s all a little bit of a perfect storm. Fascinating read.