What if, after the Battle of First Manassas (Bull Run), the commanding Confederate General Joe Johnston decided to throw caution to the wind & conducted a vigorous pursuit of the routed Union army. Considering Johnston was well versed in Napoleonic warfare, this far from impossible & plausible. Furthermore, considering the famed fortifications of Washington D.C. were far from even being started, at this stage in the war, Washington itself could have been occupied, albeit with major effort. So what impact would have a more aggressive Johnston had on the opening rounds of the Civil War? If Washington had fallen to the Rebs, what does this mean for the Union? Where is the new capital relocated & does it remain at this other city even if Washington is recaptured at some point? What strategies are then put in place by the two sides given the changes to the timeline? Anything else?