I agree with Malcolm I'm afraid; unless you understand the language you are just singing the tune - a bit like eating the crust and throwing the rest of the pie away.
The beauty of (Irish or Scots) Gaelic songs lies in the combination of the imagery of the poetry and the air and, as with any language, they only come to life in a language you are comfortable in.
Jim Carroll
PS I wonder why people have to reduce a discussion to sewer level with terms like 'folk fascist', and, as far as I have seen nobody is limiting
"your repertoire to songs from within a twenty mile radius of where you were born".