According this graph posted by the Centre for London, Seattle is in the community of world cities...

Seattle has the assets but needs more buzz and a distinct brand. What could give our city a better brand? The rain, that thing from space, the fish-throwing are not leaving a strong enough impression on the global imagination. Maybe Seattle should consider socialism. Thomas B. Edsall at NYT:
Decades of globalization have been accompanied by diminishing opportunity for those in midlevel jobs; by stagnant wages, especially for men without college degrees; and by the virtual collapse of private-sector unionization.

Standing in opposition to these adverse trends, a wave of newly elected mayors from New York to Seattle has taken office committed to deploying the power of city government and aggressive wage and tax policies to attack inequality and revive social and economic mobility.

If $15 and Sawant are the stories that are generating the kind of buzz that might improve Seattle's standing/branding in the community of world cities, and improved standing/branding translates into better visibility, and the more visibility a city has the easier it is to market itself, then socialism might actually be good for business.