Why did Federalists target immigrants in the Alien and Sedition Acts?

Many immigrants were from France.

Many immigrants supported the Federalists.

Most immigrants were not citizens.

Most immigrants supported the Democratic Republicans.

Most immigrants were not citizens

Most immigrants supported the Republicans

Explanation:

The Alien and Sedition acts were established under the excuse that war with France was inevitable, and therefore, it was necessary to protect the country from seditious and treasonous individuals. This, however, was mostly a way to weaken Thomas Jefferson's influence and chances to win the upcoming elections, since most immigrants openly supported him.

You can see that the 4th of these laws was the Sedition Act, and its only purpose was to directly punish those who speak against the Federalists.