Re the $$ Apple keeps outside of the US, no US taxes are owed on it unless and until Apple brought it "into" the US. The true problem in this situation is that US tax laws make it foolish - verging on insane - for large US companies to bring foreign earnings into the US.
Apple has glorified screwdriver plants in Ireland and in Elk Grove, CA. Computers built to a standard configuration come in the door and go by one of two routes back out the door. Most (?) go right back out again, as this is the standard configuration being sold. The rest have drives changed or added, to match a new or special-ordered configuration, and then are shipped. The people who do the reconfiguring work are contractors, not Apple employees. They are called in for a few weeks, to configure a batch, and then are let go until the next batch. Rinse and repeat. That was the way it was in ~2000, when I was in the Elk Grove plant occasionally, doing tech support for one of Apple's vendors.
I'd agree that this sucks for some one wanting a full-time career-job. But what would be a realistic alternative mode of operation? Building iMacs and MacBooks in the States? The price Apple would have to charge would be so high that even most Apple-philes couldn't/wouldn't buy them. Hire fewer people for the configuring, and do the work continually and a little more slowly? Still results in higher prices, and leaves Apple less responsive to changes in demand. This, too, is a situation at least partly driven by government - high tax rates, high cost of living due to no-growth housing policies, the cost of ever-changing enviro-regs, and more.
