Why ship European cargo directly to the US West Coast?

Why send European cargo to the US West Coast instead of using an eastern port such as Baltimore?

Cyclic says that cargo destined for western states can be cheaper to move by sea than through congested eastern ports and the transcontinental rail system.

A follow-up asks why European cargo would travel to the West Coast instead of arriving at Baltimore or another eastern port. Cyclic makes the destination central to the answer, using California, Washington and Oregon as examples. He argues that an ocean route can be cheaper than using congested eastern ports and moving cargo across the country by rail. He also contrasts the movement of freight towards and away from Chicago. No freight-rate comparison is supplied.