I'm not sure I would call this Knopfler's most famous composition.
What about "Sultans of Swing" or "Walk of Life" or "Romeo and Juliet" or "Brothers in Arms" or "Money for Nothing" or even "Sailing to Philadelphia"? Or in terms of scores, even "Local Hero"?
Mark Knopfler is a wonderful songwriter. His scores are essentially instrumental versions of his song style.