London Calling was widely praised for successfully broadening the Clash’s musical boundaries but it is important to note that it also found the group broadening their lyrical concerns from a local to a global level. A great example of this growth is "Spanish Bombs," a rousing rocker with a Spanish-themed political bent. The rich, visual lyrics of this song divide their time between strong images like "bullet holes in the cemetery walls" and passages that pay tribute to the revolutionaries of Spain’s past ("The hillsides ring with ‘free the people/Or can I hear the echo from the days of ‘39?"). The music behind this complex scenario pursues a straightforward with simple but catchy verses and chorus that hypnotically ebb and flow from peak to valley and back again. The result is simple enough to allow the lyrics to take center stage but melodically strong enough to stick in the memory. The Clash’s recording applies maximum energy to the song, layering a combination of languid power chords and quickly-strummed acoustic riffs over a throbbing rhythm section anchored by Paul Simonon’s percolating bassline. Mick Jones and Joe Strummer top it off with rousing unison vocals that provide a perfect finishing touch for this bracing rocker. This combination of thoughtful lyrics and an energetic performance made "Spanish Bombs" a highlight of London Calling and it remains a favorite with Clash fans today.