On Thursday, July 5, New York City Mayor Bill de Blasio, with no advance notice to the public he serves, jetted off to Hamburg, Germany, to attend the G-20 Summit, where heads of state and leaders or representatives from worldwide organizations and entities meet to discuss global imperatives. The mayor is not there to participate in the open dialogue between more than 20 participating countries and scores of international organizations and invited guests. He is to be the keynote speaker for an event called Hamburg Shows Attitude, which is described as a protest really for “democracy and human rights.” He...