Jason, your English is extremely good!

Re Dave Van Ronk's song, I think "Mourn your dead land of the free" may have been meant to be ambiguous.

Although most US and British people speak English, I suspect that it's easier for Brits to understand American songs than the other way (a)round. This is because American popular culture has increasingly dominated over the past 100 years. I'm not being offensive, it's simply a fact of life.

There are times when it's difficult to understand songs. Especially when they are learnt from records. For instance, I and many others spent a few years deciphering Richard Thompson's lyrics on his first solo record. Mainly because his voice was mixed pretty far back, but also because he was, I guess, trying out a new "old fashioned" way of writing.

So yes, native English speakers have problems too!