Bryce Harper, 19, is about to make his Nats Park debut in less than two hours. He is potentially the highest impact player the Nationals will ever have given his power, speed, and drive. One sportswriter likened him to Pete Rose, though Rose didn't go for the long ball often.
Harper is probably capable of hitting 40-50 homeruns in a season. I say probably because he has yet to fully develop physically.
Washington hasn't ever had a position player with this talent to my knowledge. Walter Johnson, a century ago, dominated the game from the mound and helped the old Senators win a World Series in 1924. The city now has Steven Strasburg to lead its incredible pitching while the young phenom Harper matures and develops and hopefully beefs up its batting.
Another World Series could be on the horizon. Let's hope its an "event horizon."