The way it should work is:
- Apple makes an iPhone for $200 in China
- Apple sells the iPhone in the US for $600
- Apple pays US taxes on the $400 profit
The way it actually works is:
- Apple creates Apple of Ireland as a PO Box in Ireland
- Apple gives one of its iPhone patents to Apple of Ireland
- Apple makes an iPhone for $200 in China
- Apple sells the iPhone in the US for $600
- Apple pays $400 to Apple of Ireland to "license" the patent
- Apple pays $0 of US taxes because it sold the iPhone "at cost"
- Apple of Ireland pays negligible taxes on the $400 profit due to low tax rates