They believed that expansion went against American ideals.
An antiimperialist is a person who is opposed to imperialism.
The Republicans.
they opposed it
Lincoln was opposed to the expansion of slavery
The anit-imperialists opposed the United States expansion because they felt that imperialism would violate the fundamental principle that just republican government must derive from consent of the governed.
Although originally a supporter, Quincy opposed westward expansion by 1843 because of the consequent expansion of slavery into Texas.
The Free-Soiler party opposed the expansion of slavery into territories gained by the Mexican Cession.
Rufus King
Free Soil Party, opposed the expansion of slavery
There was no opposition to the westward expansion of the US. The first available westward movement came with the Treaty of Paris, where England gave to the 13 colonies all land east of the Mississippi River. Also, the Louisiana Purchase in 1803 set the groundwork for westward expansion.
to end the napoleon wars Actually the US declared war because Britain opposed US expansion and trade with France, supported native American tribes against the US and press-ganged (forced) US sailors to fight in her navy.
Democracy