TrueBlue partners already include AA, EI, and QR, so the case exists.

Interestingly, SQ is no longer listed on their partners page, though a page for SQ still exists. Not sure if this is ...... IT or if something is actually going on here.

Personally, I don't see the benefit to OneWorld in having a third US airline as a full member -- while the customer experience would benefit, the unreliability would drag everyone else down. The most logical way I could see it happening is through a merger with AA or AS, but not joining on their own.

-J.