Turkish President Recep Tayyip Erdogan has never made a secret of his ambition to become a historic regional leader. His nostalgia for the Ottoman Empire long ago became a source of concern for observers who think he might seriously attempt to bring it back. His detractors mock him as “Sultan Erdogan,” but he might not find that name insulting. Erdogan flexed his military muscle in several recent conflicts. He might be warming up for something bigger, or he may have already overtaxed Turkey’s military strength.