Good points in this thread but it's a bit incomplete. You might think ahead for a national socialist takeover and the merging of all airlines into one. This might seem like a far fetched concern but remember that, save for a few fringe lunatics, no one saw COVID coming either. A coup is the most common method of changing government and these happen quickly taking many by surprise. Our defense community has already warned that right wing extremism is the biggest threat to national security, and many extremist cells are poised to thrust the pendulum, which is already in motion to the right. Tucker Carlson is the most popular cable news/entertainment show and Musk's takeover of Twitter has driven it into a jingoistic frenzy citing Fentanyl importation and population replacement. Add a populace that's proven to set aside individual liberties for an illusion of safety and the stage is set. The most likely scenario is a date of hire merger however United is experiencing contract difficulties which could place it decidedly below Delta in career expectations, blurring the calculus. Also consider that international travel is likely to be severely restricted for at least five years under onerous entry and immigration requirements, and this could have a severe impact on United's core business while Delta remains insulated from such difficulties through its international code share agreements. In light of these complications I estimate that a move to Delta should prove neutral to beneficial, however a move from Delta to United exposes one to the aforementioned risks. One factor that may offset risks in favor of a move from Delta to United is being home based, as commuting may prove impossible as states quarrel. Definitely weigh ports, manufacturing, and natural resources when choosing a crew domicile.