 Why did the Viceroy blockade the Earth if he wanted an Earthling to come and meet with him?
The sight of an Earthman on Vega III, where it was impossible for an outlander to be, brought angry crowds to surround John Crownwall as he strode toward the palace of Viceroy Tronn Ffallk, ruler of Sector XII of the Universal Holy Empire of Sunda. "If you wanted someone from Earth to come here to see you, why did you put the cordon around Earth? There was even serious discussion of destroying Earth out of hand, while it is still possible. While these creatures could by no means be classed among the intelligent races, there was a general expectation, which we reported to the Sunda, that they would some day come to be numbered among the Servants of the Emperor.
 The blockade was a test to see if Earthlings were smart enough to help the Vegans defeat the Sundans.
 The blockade was a test to see if Earthlings were smart enough to help the Vegans defeat the Sundans.  The blockade is there to protect Earth from the Sundans.  The blockade is there to quarantine the Earth. Earthlings may have diseases that could infect the other races.  The blockade is there to keep people from leaving the Earth.