California expansion by Alaska and Southwest reflects healthy competition in a dynamic market

In the mature US aviation market expansion opportunities tend to centre on airlines playing to their strengths, connecting the dots in their respective networks to maximise geographical value. That is the path Southwest Airlines is adopting with its recent expansion in California, adding service from airports where it has a commanding presence into markets where it is equally strong.

Of course, Southwest's expansion from California is occurring as Alaska Airlines leverages its newfound strength in the state after acquiring Virgin America. The message the new routes send is not subtle - Southwest has no intention of allowing its strength in California to wane.

However, the competitive overlap with Alaska on Southwest's new flights to the Californian cities of San Jose and Sacramento is minimal, and the push appears to be an offensive move by Southwest to fill in network holes and capitalise on the stable economy of Northern California.