Roy Lichtenstein was am American pop artists; his style was a comics style with very recognizable dots all over the picture, creating an illusion of poster scale printing. In fact most of his paintings are drawn using acrylic paints and stencils to create a proper dot grid.
The concept this time was pretty simple: a guy, a girl and a gun - what's not to love; on the technical level it had to be acrylic paint and benday dots:
Alexandra, Lieutenant Bunners shot down