Freedom of speech means you are entitled to voice whatever you want to say. However, freedom of speech does not give you the right to anything without consequences to the law ie. if you defame, libel, lie or threaten anyone there are laws to prevent it. During war time free speech can get one a treason charge.One reason would be to prevent supporters of the enemy from creating an atmosphere of low morale by constantly disparaging the reasons that we are at war. One government law passed during wartime which limited the freedom of speech to protect national security issues was the Sedition Act of 1918.