First, it's worth noting that most of the <300nm fabs in the U.S. are really new. The Oregon facility was historically the most relevant fab, Arizona seems to be (potentially?) supplanting it from a design and capacity POV.
But the Israeli fab really shouldn't be discounted, they employ 12k people in Israel. I can't find numbers on production output, but that headcount is a similar OOM to the Oregon plant. Most of their successful, recent designs came from Israel, too. The Ireland fab employs 4.5k people. There's 22k in Oregon, unclear on the breakdown of manufacturing and R&D/non-manufacturing roles.
As I understand it from said rabbit hole, they do a lot of design and "proofing" manufacturing of low-nm processes in Oregon, but rely on Ireland and Israel to scale-up.
It seems that the recent (i.e. post-9/11) Arizona plants are more geared towards high-volume production. Regardless of what calculations went into those decisions, they're a hedge against political instability in Israel.
Their consumer and server business (read: low-nm) processes are largely international.
The wikipedia page you linked evinces this statement.
The phrase "most of its manufacturing" is a Simpson's Paradox statement. It's true, but not in a way that's interesting. High-nanometer processes are easier to automate.