Final answer:
The 1796 letter refers to the Alien and Sedition Acts of 1798, which aimed to prevent the French menace but limited civil liberties and led to significant political opposition and discussion about states' rights.
Step-by-step explanation:
The 1796 letter to a Philadelphia newspaper refers to d) The Alien and Sedition Acts. These acts, passed in 1798, were designed to protect the United States from the perceived French threat but ended up undermining Federalist power by targeting immigrants and essentially limiting freedom of speech and the press.
Democratic-Republicans, including Thomas Jefferson and James Madison, opposed the acts through the Virginia and Kentucky Resolutions, arguing that they were unconstitutional and an infringement on states' rights. This turmoil was a result of increased partisan politics following the XYZ Affair and the Quasi-War with France.