Sometimes, a single act can reveal everything there is to know about someone or something. The attack by the Taliban last week on a 14-year-old Pakistani girl, Ms. Malala Yousafzai, is one of those clarifying moments. The assassination attempt was a cowardly, barbaric deed. A political movement that feels threatened by a 14-year-old child deserves to be isolated, humiliated and disregarded, both for its savagery and for its utter disregard of the rules of normal politics. Now there can be no doubt about what the Taliban stands for or what it will do to realize its ambitions.

Ms. Yousafzai has been a relentless campaigner for the right of young Pakistani girls to an education. In 2009, at the age of 11, Ms. Yousafzai began a journal for the BBC, the British broadcaster, in her native language of Urdu. Writing under a pseudonym, she explained the perils and deprivations of life under the Taliban in her home in the Swat valley of Pakistan, a picturesque region sometimes called "the Switzerland of Pakistan." When the Pakistani military drove the Taliban from the valley, she became even more outspoken, focusing on her desire for an education and the importance of education for young women — a practice that was banned by the Taliban, which they enforced by threatening students and teachers, and escalated to the blowing up and burning down of schools for girls. Her efforts won her a national peace prize, one of the country's highest civilian honors.

It also earned her the enmity of the Taliban. The group reportedly warned her and her family three times to stop her advocacy and to shut down their education efforts — her father runs the school that Ms. Yousafzai attends. They refused to bend, and their determination prompted the Taliban leadership to decide two months ago to proceed with the attack. According to Taliban spokesmen, they selected three men, two of which were trained sharpshooters, to study the girl's route home from school. On Oct. 9, they attacked the school bus in which she was traveling, and shot her in the head and neck, and wounded two of her class mates. While her injuries are severe, it appears as though she will survive and recover.