...The objection has also been made that the principle as to immunity from previous restraint is stated too broadly, if every such restraint is deemed to be prohibited. That is undoubtedly true; the protection even as to previous restraint is not absolutely unlimited. But the limitation has been recognized only in exceptional cases. 'When a nation is at war many things that might be said in time of peace are such a hindrance to its error that their utterance will not be endured so long as men fight and that no Court could regard them as protected by any constitutional right.' Schenck v. United States, 249 U. S. 47, 52, 39 S. Ct. 247, 249, 63 L. Ed. 470. No one would question but that a government might prevent actual obstruction to its recruiting service or the publication of the sailing dates of transports or the number and location of troops.6 On similar grounds, the primary requirements of decency may be enforced against obscene publications. The security of the community life may be protected against incitements to acts of violence and the overthrow by force of orderly government. The constitutional guaranty of free speech does not 'protect a man from an injunction against uttering words that may have all the effect of force. Gompers v. Buck's Stove & Range Co., 221 U. S. 418, 139, 31 S. Ct. 492, 55 L. Ed. 797, 34 L. R. A. (N. S.) 874.' Schenck v. United States, supra. These limitations are not applicable here. Nor are we now concerned with questions as to the extent of authority to prevent publications in order to protect private rights according to the principles governing the exercise of the jurisdiction of courts of equity...