Into the Wardrobe

I wonder if CS Lewis wrote anything about patriotism. This is still a very vivid and sometimes controversial issue in my country, and I would like to know what Lewis thought about it. Many people say that patriotism is something positive, but I still have my doubts. It would be good to know Jack's opinion. To be honest, his book Till We Have Faces, which I read just this year, was a breakthrough in my thinking about what true love is, in contrast to what I imagined to be love prior to reading this book. So I think that his advice about patriotism will be very precious. I would love to read some key quotations. Thank you in advance.

There's quite a bit in the second chapter of The Four Loves, the one titled Likings and Loves for the Sub-Human. A tiny bit more in The Screwtape Letters, numbers 5 and 7.