But in the end US defeated the british and canadian guys and nothing changed(no lands taken or lost etc).
Xerxes also burned Athenas, but the Greeks won.
Actually, the way you wrote that sentence promotes that you think the Canadians/British were trying to take American land. In reality, it was the other way around.
The war of 1812 is considered by most to be a "tie" or "un-won" war as there were no benefits for neither the Americans nor the Canadian (British included) side. However, the only "losing" side were the Aboriginals who lost land even though they were promised land by the British government (Who originally wanted to create a large section of land for the aboriginals). When the white flags were put up, both the Americans and British/Canadians agreed to not drop any land of their own and set the current standing boundaries.
However, considering the fact that the American's main goal was to gain more land while the British were dealing with Napoleon, and as such they failed in doing so... by definition of Attack/Defend, the British and Canadians could be considered the victorious of the War of 1812.
Then Canada gained independence and the star spangled banner became the national anthem for the US. The end.
Good Documentary if interested:
https://www.youtube.com/watch?v=M-bC2TWTGyQ