I agree, I have flown direct non stop from Los Angeles to Narita airport in Japan enroute to Singapore via Hong Kong. same route back and it was non stop, no need to refuel Narita to Singapore is several hours, the stop in Alaska is the closest American soil flying across the north pacific and it was said specifically to refuel, probably to make the hop from there to DC would make sense.
6500 mile is max range for a 747 safely
4,830 miles distance from Hawaii to DC
3,369 miles distance from Anchorage to DC
Singapore is a great city, crowded but not like Hong Kong
Interesting, very interesting
That is the range for a commercial 747, NOT AF1