Matt Yglesias is wrong about the similarity between conservative and liberal patriotism as I think there is a very clear difference between the two.
I would classify the conservative view of patriotism as 'childlike' and liberal patriotism as 'adult' in that a traditional conservative's love of country matches the love a child feels for its parent and the liberal's love of country matches the love an adult feels for his or her parent. As a child, my parents existed as infallible beings and my love for them was unquestioning. Conservatives view love for country in the same way- the entire 'Love it or Leave it' serves as a testament to this world view.
For liberals however, love of country is complicated -just like the love I feel for my parent's is complicated. As I have gotten older, I see my parents as human and capable of making mistakes. Yet, it is their humanity which makes them all the more lovable (and sometimes maddening).