A new Alaska Airlines lounge at Seattle-Tacoma International Airport (SEA) will soon become the largest lounge for any airline in the U.S. The two-story, 40,000-square-foot lounge will be a part of SEA’s expanded C Concourse, with each story measuring roughly 20,000 square feet. Spike O’Neill, co-host of “The Jake and Spike Show” on KIRO Newsradio, raved about the new addition, noting it’s a ‘privilege’ to be admitted into such a prestigious clu…