Cartoons originally published by the French newspaper, Charlie Hebdo, were the fundamental factor that led to the Charlie Hebdo shootings in 2015, for which a terrorist group of Al-Qaeda and the Islamic State of Iraq and Syria (ISIS) took responsibility. Since then, there have been acute conflicts between Europe and Islamic extremists, and the risk of terrorism still looms in Europe. In early October this year, Samuel Paty, a French middle-school teacher, held a class on freedom of expression with Charlie Hebdo's cartoons, which satirizes the Islamic prophet, Muhammad. As a consequence, Mr. Paty was beheaded on October 16th by an 18-year-old Islamic extremist. Also, on October 29th, an Islamic extremist attacked several people in the Notre- Dame basilica and virtually beheaded an older woman in the church. Even on November 11th, at least three people involving European diplomats were wounded from an explosive attack from an extremist at the international ceremony commemorating the end of World War I in Saudi Arabia. Putting together these incidents, the threat of terrorism from the Islamic extremists to Europe has raised to the surface again recently since the French middle-school teacher, Paty was murdered. Terrorism in Europe has been observed frequently.