as a secondary cause after maritime issues, noting that many historians have mistakenly rejected expansionism as a cause for the war. He notes that it was considered key to maintaining sectional balance between free and slave states thrown off by American settlement of the Louisiana Territory and widely supported by dozens of War Hawk congressmen such as Henry Clay, Felix Grundy, John Adams Harper and Richard Mentor Johnson, who voted for war with expansion as a key aim. However, Horsman states that in his view "the desire for Canada did not cause the War of 1812" and that "The United States did not declare war because it wanted to obtain Canada, but the acquisition of Canada was viewed as a major collateral benefit of the conflict". However, other historians believe that a desire to permanently annex Canada was a direct cause of the war. Carl Benn notes that the War Hawks' desire to annex the Canadas was similar to the enthusiasm for the annexation of Spanish Florida by inhabitants of the American South as both expected war to facilitate expansion into long-desired lands and end support for hostile tribes (Tecumseh's Confederacy in the North and the Creek in the South). Alan Taylor says that many Democratic-Republican congressmen such as John Adams Harper, Richard Mentor Johnson and Peter Buell Porter "longed to oust the British from the continent and to annex Canada". A few Southerners opposed this, fearing an imbalance of free and slave states if Canada was annexed. Anti-Catholicism also caused many to oppose annexing the mainly Catholic Lower Canada, believing its French-speaking inhabitants unfit "for republican citizenship". Even major figures such as Henry Clay and James Monroe expected to keep at least Upper Canada in an easy conquest. Notable American generals such as William Hull issued proclamations to Canadians during the war promising republican liberation through incorporation into the United States. General Alexander Smyth similarly declared to his troops when they invaded Canada that "you will enter a country that is to become one of the United States. You will arrive among a people who are to become your fellow-citizens". However, a lack of clarity about American intentions undercut these appeals. David and Jeanne Heidler argue that "most historians agree that the War of 1812 was not caused by expansionism but instead reflected a real concern of American patriots to defend United States' neutral rights from the overbearing tyranny