Lichtenstein's version of pop art was just as shocking as Andy Warhol's; in 1964, Time magazine had asked "Is he the worst artist in America?" In this picture and many others Lichtenstin uses theBen-Day dot, a technique for printing shading on a regular printing press (similar to pixellation in the digital world), but he scales it up dramatically so that the viewer is conscious of the technique being used.
Technically, this is a tour de force - the difficulty of making by hand something that looks as if it was mechanically creatd shouldn't be underestimated. Unlike the 'war' paintings which Lichtenstein copied from comic books, this appears to be an original conception, but he continues to use the style of a printed comic, including the speech balloon.
Through the medium of the song Lichtenstein makes the viewer think about love and loss and memory, but also about the nature of art. What is popular, what is vulgar, what is 'high' art? Jazz, like comics, is a popular art form that later became taken seriously; in this print, Lichtenstein is asking questions about the status of jazz, as well as about our assumptions about the respective places of fine art and comics, craft and mechanical reproduction.
The image of a girl with a microphone, singing a jazz song, her face clearly expressing the sad emotions she is calling up, also suggests the music she's singing through the musical notes added to the speech balloon, but of course the viewer can't hear it - another level of conceptual complexity added to the work. Lichtenstein intends to provoke the viewer to serious thought.
Like Lichtenstein's other paintings of this period, this is a noisy and intense image, about big emotions. Although his style may appear mechanical and even clinically precise, he tackles highly emotional and action-packed scenes. His art may be easily datable by its references to pop culture, but it's about things that mattered to Americans of his day - and to us now.