Imperial Europe

What if Europe was ruled by an Emperor (or a ruler with as much power)? They would be able to do what they wanted with Europe. Would they be able to rule as an Augustus, a Victoria, a Hapshepsut or a Thomas Jefferson? or would they be more like a Napoleon or a Julius Caesar? or worse would they be a Hitler, a Stalin, a Nero or a Bush? Would they be, like the first category, an intelligent, prosperous and maybe even loved ruler? Would they be, like the second category, a ruler just as intelligent but martial and maybe short lived? or would they be, like the last category, a cruel, barabarian, military (or not) ruler, hated by his subjects and shunned by the rest of the world? Would even be possible to become emperor of Europe. If people stop caring about politics, yes. If there is a serious crisis (economical, political or social) and Europe needs to be united, yes. If the European Union becomes the United States of Europe and its president is weak and incompetent, yes. If Europe continues to become more and more like the U.S.A. then it will certainly possible to seize power as Europe becomes more and more united. It may not be possible at this very moment, but in a few generations, maybe. Europe could take its place as world power, place that it lost as England, France, Germany, Spain, Portugal, and the Netherlands, place that it could retake as Europe, as the Empire of Europe!