Final answer:
The laws prohibiting protests against the U.S. war effort directly weakened freedom of speech protected by the Constitution.
Step-by-step explanation:
The laws prohibiting protests against the U.S. war effort directly weakened (C) freedom of speech protected by the Constitution.
During times of war, such as in the example of the Espionage and Sedition Acts, the government passed laws to limit dissent and argued that it was necessary for national security. The Supreme Court, in the case of Schenck v. United States, ruled that such laws were justified to protect the safety of the United States and the military.
In more recent times, the press has been able to successfully argue for the protection of freedom of the press based on the public's right to know. An example is the case of the New York Times publishing the 'Pentagon Papers' during the Vietnam War.