I can't think of when I last saw a more offensive portrayal of the Irish, they all come across as a load of uneducated, backwards, bullies.
To the average American Ireland may seem the size of a small city but it's a modern country with a rich culture and heritage.
County Wexford, where Walter comes from has museums, universities, teaching hospitals, technical colleges and a long and proud history of heroes and rebels. Ireland has one of the best education systems in the world, even in the tiny village Walter comes from the people still went to school, they aren't surprised or confused by chemical reactions. And they don't need to be sent instructions on condensation collectors, or need "genius" help to predict or prepare for the regularly recurring droughts.
Also, anyone over the age of about 8 who acted like the two bully neighbours would have got a thick ear from the nearest parent.....and probably the priest and learned what is acceptable behaviour long before they were adults. Outside America we call an adult punching someone assualt and they get arrested, the village doesn't gather to watch a school yard fight. And regardless of any strained relationships family doesn't sit back and watch someone get picked on and abused at their own sisters memorial!