Who loves their flag, using jackhammers, and precise measurements? Your military officer! He's always saluting the flag, jackhammering near all the new recruits to test them, and checking the measurement between the floor and their pants. Who else could it be?
That military officer's favorite bird is an eagle (い)! That should be obvious because the eagle is the bird of America! And that's the country he fights for!
Currently there are no similar looking kanji which exist in the WaniKani learning system