To civil libertarians, the conviction of Tarek Mehanna for aiding Al Qaeda dangerously undermined free speech rights, and delivered a stark message that holding radical ideas can be punished under the guise of national security. To terrorism specialists, the jury’s swift guilty verdict validated the government’s efforts to prosecute domestic terrorist suspects, and sharpened the often hazy line between protected speech and active support for terrorism. The polarized reactions to the high-profile case mirrored the contrasting arguments in court, where the Boston-area extremist was described as both