New York Mayor Bill de Blasio places flowers near a sign reading "Courageous police, gendarmes, thank you" in front of the Hyper Cacher kosher supermarket in Paris on January 20, 2015, for the victims of the hostage-taking by jihadist gunman Amedy Coulibaly at the Jewish supermarket at Porte de Vincennes which left four dead on January 9. (credit: JOEL SAGET/AFP/Getty Images)
Mayor Bill De Blasio In France
New York Mayor Bill de Blasio prepares to place flowers in front of the Hyper Cacher kosher supermarket in Paris on January 20, 2015, for the victims of the hostage-taking by jihadist gunman Amedy Coulibaly at the Jewish supermarket at Porte de Vincennes which left four dead on January 9. (credit: JOEL SAGET/AFP/Getty Images)
Mayor Bill De Blasio In France
New York Mayor Bill de Blasio places flowers near a sign reading "Courageous police, gendarmes, thank you" in front of the Hyper Cacher kosher supermarket in Paris on January 20, 2015, for the victims of the hostage-taking by jihadist gunman Amedy Coulibaly at the Jewish supermarket at Porte de Vincennes which left four dead on January 9. (credit: JOEL SAGET/AFP/Getty Images)
Mayor Bill De Blasio In France
New York Mayor Bill de Blasio prepares to place flowers in front of the Hyper Cacher kosher supermarket in Paris on January 20, 2015, for the victims of the hostage-taking by jihadist gunman Amedy Coulibaly at the Jewish supermarket at Porte de Vincennes which left four dead on January 9. (credit: JOEL SAGET/AFP/Getty Images)
Mayor Bill De Blasio In France
Mayor of Paris Anne Hidalgo (R) poses with Mayor of New York Bill de Blasio holding a book by late French cartoonist Cabu, who was killed on January 7 during an attack on the offices of French satirical weekly Charlie Hebdo, during their meeting at the City Hall of Paris on January 20, 2015. (credit: JOEL SAGET/AFP/Getty Images)
Mayor Bill De Blasio In France
Mayor of Paris Anne Hidalgo (R) speaks to Mayor of New York Bill de Blasio during their meeting at the City Hall of Paris on January 20, 2015. (credit: JOEL SAGET/AFP/Getty Images)
Mayor Bill De Blasio In France
Mayor of Paris Anne Hidalgo (R) meets with Mayor of New York Bill de Blasio (2nd L) during their meeting at the City Hall of Paris on January 20, 2015. (credit: JOEL SAGET/AFP/Getty Images)
Mayor Bill De Blasio In France
Mayor of New York Bill de Blasio and Mayor of Paris Anne Hidalgo place flowers near the offices of French satirical weekly Charlie Hebdo in Paris on January 20, 2015, to pay tribute to the twelve people killed when gunmen armed with Kalashnikovs and a rocket-launcher opened fire in the Paris offices of Charlie Hebdo on January 7. (credit: JOEL SAGET/AFP/Getty Images)