Lyric discussion by Bulgaroktonos 

Cover art for Bombers Bay lyrics by Echo and the Bunnymen

I think it's about the British experience in World War II. Berlin to Bomber's Bay (Bombay, India). Mandalay is in Burma, which was the scene of the British contribution to the Pacific War.

My Interpretation

@Bulgaroktonos That seems basically right, although Madrid and "pack up your troubles" don't match WW2. It may be about the British experience in all the wars of the 20th century. It may be about some literary work of which I'm not aware about all those wars ~1915-1945.