As a matter of fact, my youngest daughter asked me that very question this evening at dinner when we were talking about this article.
I really didn't know how to answer her.
Mount Rainer is a dormant volcano, as was/is mt. St. Helens. Mt Rainer would most likely, according to scientists, produce huge mud flows moving toward Tacoma area. Pretty much wipe out everything in its path. I must say, mt Rainer is a beautiful mountain.