Well for the most part they sat out the war, in their so called "emergency", but had the Germans or English invaded they would have put up some kind of fight. In the case of England invading it would have not been long, as they never had much in the way of ammunition, being dependent on UK supplies.
Fredrick, you've left me somewhat speechless!
Is there seriously a view in the US that Britain would have even contemplated invading Eire??