Quiz any fan of soccer in the US as to the origin of the professional game on American soil, and you're likely to get a myriad of answers - usually rooted in generational identity.   ​If you're under 30, the 1996 launch of Major League Soccer looks like a logical starting point - 25 years old, 29 teams strong, and dozens of soccer-specific stadiums befitting a "major" sports league.   Older MLS fans in places like Seattle, Portland, and San Jose point out the original versions of their current clubs being domiciled in something called the North American Soccer League - which featured a bevy of international stars and drew huge crowds in the late 1970s/early 1980s as the then-"sport of the future."   Others with longer memories (and often soccer-playing lineages) will recall the decades-long, ethnically-flavored heartbeat of the sport known as the American Soccer League - dating back to 1933, or even 1921, depending on your guideposts.   But, as soccer historian Dr. Brian Bunk ("From Football to Soccer: The Early History of the Beautiful Game in the United States") reveals to us this week, the true birth of the pro game dates all the way back to 1894 - when not one, but two leagues sought to bring England's popular fast-growing sport to the colonies - introduced (interestingly) with the financial backing and operational resources of baseball's National League.