I disagree on this part. PDX-SEA is a <45 minute flight that currently runs about 15 times/day (and was even more in the pre-Covid days). PDX is a major Mileage Plan city as well; it's very conceivable that someone that really wants to earn their AS status might choose to go PDX-SEA-NRT to earn their miles rather than take PDX-HND on a less-than-daily basis. Right now, the fact that Delta would be flying into Haneda on a less-than-daily basis basically offsets the fact that JAL goes into Narita from Seattle (HND the better airport, JL the frequency advantage). As AA (and OneWorld) build up Seattle international flying, that makes them much more compelling to a Portland-based flyer. Right now, if you're a primarily international flyer out of Portland, DL makes more sense since you can do that quick hop to SEA and go to Asia or Europe; OW building up Seattle will help make them a more compelling option, and then when you combine that with the fact that AS has a domestic operation out of PDX that runs laps around DL there, and it can help build an even stronger, more loyal base.
If there is a nonstop option available, I think any corporate customer would take that over a connection, even if it's just a 45 minute hop to Seattle. If that weren't the case, then there would be no PDX-TYO flight at all. AA announced plans to build up a SEA TPAC gateway before COVID hit (February 2020, IIRC), and JAL was flying SEA-NRT in 2019, long before that announcement was made, and relied on AS connecting passengers through SEA at that point. I'm guessing that a good handful of those passengers on each daily flight were from Portland, probably those with an AS mileage plan. At that point, DL still had plans for a daily PDX-HND flight. The less than daily schedule for Delta on PDX-HND now is currently reminiscent of the airlines not really knowing a solid timeline for when international travel will begin to resume, and nothing to do with OneWorld in SEA.
Never was it my point that AA expanding in SEA is what would lead to DL dropping PDX-HND. It was that AS joining oneworld that would make the difference, because of two reasons:-
(a) JL was rumored to be considering NRT-PDX with Zipair.
(b) We never got to see fully how successful DL will be after they move everything to HND.
I agree that the route has succeeded with contracts & for the most part of history with onward feed at NRT with the intra-Asia routes. PDX-NRT was always one of the routes that DL reduced the frequencies in, and are now. Of course, it is my personal interpretation that the contracts alone are insufficient to maintain it at 1x daily. But I stick to my hypothesis that the days of a SkyTeam carrier’s niche on P2P route between two oneworld hubs is numbered. I am happy to be proved wrong, but either way we’ll see soon.
As for when BA launched PDX-LHR, DL only announced their intention to launch SEA-LHR, without DL/VS making any deletions to their LHR routes. They never touched the inventory on PDX-LHR. DL loaded SEA-LHR much later after they dropped several LHR frequencies along with PDX. Given just that, there is no reason to believe that they intended to fly both PDX-LHR and SEA-LHR.
Fair enough, apologies for misinterpreting your initial post.
I guess I just don't think that AS joining OneWorld automatically makes PDX a OneWorld hub. IMO, there wouldn't be much of a point in JL adding NRT-PDX now because that would potentially take away passengers from their NRT-SEA flight. NRT-SEA is obviously the higher yielding route of the two, so JL would need as many passengers on that flight as possible. Not to mention that AS has a lot more connecting flights available for JAL's passengers in SEA than they do at PDX. However, if JL did add NRT-PDX, they might have the potential to take away the local O&D traffic and Portland-based AS loyalists with an AS mileage plan, but it would still be a very big risk for JL to do this.