There's also the issue that a hub should have at least some o&d demand, and most of that went out the window for NRT after HND got serious about international flights again.

AA and UA have stuck around NRT a little though because each has revenue sharing JVs with Japanese airlines and some connections (e.g. mostly vacation destinations) still work better at NRT than HND.

Switching topics to this quote from the Op (sorry for the spoiler tag; that was a mistake that I don't know how to undo)Delta also flies from SEA to HND, PVG, and TPE is in the works, if it hasn't launched already.

But, if you want to get to Guam without leaving the US, UA via HNL might be a better option.
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