Patriotism is all well and good, and as he says, important. However there is an ugly side to it called Nationalism.
From the sounds of it he never liked Nationalism which is understandable. Now that the US was hit at home the Nationalism more closely resembles Patriotism. Our feeling of solidarity having a focus on 'survival' rather than 'being better than everyone and spreading or forcing our ideals on others'. However, nationalism is a constant under-current in any country. In extreme situations it can be a greater evil.
In short, keep patriotism in check with healthy doses of rational thought and humble pie.