Flight with connector through China is ~$200 cheaper
I found a flight from Seoul to San Diego departing on August 10th for $944 ($990 after the traveler's insurance option) that hops to Beijing and Los Angeles first.
I expect to board a ferry from Fukuoka to Busan on August 2nd (or 1st?) then take KTX (theかんこくのしんかんせん) to Seoul. That means I'll be in Korea for eight days! I would hope my family members don't mind having me lodge with them that long. If they do, I could stay with my uncle's family for half the time, then at my grandmother's for the other half. If they can't for whatever reason, let's hope they can help me find aunts-in-laws, uncles-in-laws, cousins-once-removed, and other obscure family members that are family members nonetheless. Almost everything is cheaper in Korea than Japan, but I think the exception is taken to hotels. They're about the same rates as Japan and the US, I believe. Therefore, I cannot stay in hotels.
I hope I don't need a special visa to set foot in Communist China even if it's just for a connecting flight. I haven't been to a Communist country since '89 (seriously!) and that was to East Germany with my parents.
A domestic flight costs less than Amtrak!
Once I'm in San Diego to visit Uncle Steve and a Stephen Matheson, a missionary friend from Chula Vista (a San Diegan suburb), after 5 or so days, I'm not taking an Amtrak train this time. I found an even cheaper domestic flight! After other fees and all, they're $117-$200. I'll of course choose the cheapest option available. I assume my family will pick me up from the Mid-Continent Airport in Wichita. (In case you were wondering, Amtrak costs ~$206 now, extra added もちろん after upgrading to business-class.)
Trains are more economical than planes in Japan, but it's the other way around in America!