Story highlights Paul Callan: UK leader's suggestion to restrict websites where terrorists "breed" is wrong

Callan: Policy would violate US First Amendment's guarantee of free expression

Paul Callan is a CNN legal analyst, a former New York homicide prosecutor and currently is of counsel at the New York law firm of Edelman & Edelman PC, focusing on wrongful conviction and civil rights cases. Follow him on Twitter @paulcallan. The opinions expressed in this commentary are his own.

(CNN) Many in the United States, including the President, are likely to welcome British Prime Minister Theresa May's suggestion that it is time to place restrictions on "safe space" Internet websites, such as Facebook and Google, that allegedly allow terrorist ideology to "breed."

Her call for Internet free speech censorship was motivated by the latest ISIS-inspired slaughter of the innocent -- first in Manchester and then this weekend at London Bridge

Such a policy in the United States would clearly violate the First Amendment's sacred guarantee of free expression -- the very same principle that helped spur the American Revolution against British tyranny. This core American belief should not be tossed aside, even in the face of terrifying ISIS attacks.

The fight against "Islamist extremism" does require continued and even more aggressive military action in Great Britain and throughout the world, but that action should not take the form of restrictions on free political speech.

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Such calls for censorship always emerge when terrorists, foreign and domestic, preach and kill in pursuit of their hateful ideology. Ironically the speech requiring the strongest defense is often the most hateful speech of all. But in these cases, those who believe in freedom must stand even more firmly. Otherwise all political expression will be in danger of censorship, depending on who runs the government at any point in time.

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