Why did many Mexican-Americans join the war effort during WWll?

The main
reason why many Mexican-Americans joined the war effort can be found in the second word in the
name you have used to describe this group.  The second word in this name is Americans. 
Mexican-Americans were (and are) American.  Because they were American, they participated in the
war effort just like other kinds of Americans did.

After the Japanese
attacked Pearl Harbor, Americans were outraged.  They wanted revenge on Japan for the sneak
attack.  They wanted to defend their country against the...

href="https://hsp.org/sites/default/files/legacy_files/migrated/mexicanamericansandworldwarii.pdf">https://hsp.org/sites/default/files/legacy_files/migrated...