Why would the War of 1812 change European attitudes of America?

The Americans had peacefully settled the war.

The American had stood the British challenge again.

The Americans had opened trade with Europe.

The Americans had contained the French.

B. The American had stood the British challenge again.

The war was between America (it also included the Native Americans and the Canadians a little bit) and Great Britain, so the war and presence of troops can definitely cause some tension with the surrounding countries.