Answer:
World War I Germany's unfettered submarine warfare against American ships during World War I provoked the U.S. into abandoning the neutrality it had upheld for so many years. The country's resultant participation in World War I against the Central Powers marked its first major departure from isolationist policy.
Active, come on, you really couldn’t answer this?
Answer: search only with probable cause
Explanation:
The first 10 Amendments are meant to protect the rights of American citizens with the logic being that if these rights are included in the Constitution, it would be harder for the government to deny the citizens of it.
The 4th Amendment includes one of those rights which is the right of citizens to not be searched by agents of the government without probable cause and if this is done, whatever is found cannot be used as evidence against the citizen in question.