Why did the federalists mistrust alien act?

Federalists mistrusted the Alien Act because they feared it could be used to suppress political dissent and target immigrants who opposed their policies. Many Federalists believed that immigrants tended to support the Democratic-Republican Party, and the Act could be exploited to eliminate potential political rivals. Additionally, the broad powers granted to the president raised concerns about potential abuse and the erosion of civil liberties. The Act exemplified the tension between national security and individual rights during a politically charged era.