Greta Thunberg’s radical turn deserves scrutiny, not applause

Greta Thunberg recently traveled to France to applaud the protest movement. Wearing a black-and-white scarf associated with pro-Palestinian activism, she appeared outside a high school in a Paris suburb and lent her celebrity to demonstrations marred by rioting, arson and vandalism — with authorities already putting the damage at no less than $34 million. 

Thunberg brought the applause. Taxpayers were left to pay for the destruction.

Her appearance fits a broader pattern of increasingly...