Mock battle

Does "mock battle" mean "staged and unreal battle" that is "pretending to fight"? What is the relation of "silent witnesses or victims" with it? Does it mean "those who know about the meaningless goals behind wars and mock wars and do not talk about them and those who are killed in such meaningless wars"?

Context:

Canadian-born Philip Guston became well known after 1945 in the USA as a founder of abstract expressionism. He had earlier produced work that reflected his personal responses to war. Bombardment (1937–1938), for example, addresses the atrocities of the Spanish Civil War and reflects his knowledge of Picasso’s Guernica (1937) and the politically charged Mexican muralists of the 1930s such as Diego Rivera, whose work he knew well. Bombardment depicts civilian panic and horror at the moment of a bomb explosion. Later works respond to events of the Second World War, particularly the Holocaust (he was Jewish), and become progressively more abstract as he treats participants in mock battle or silent witnesses or victims. The 1950s, his period of success as an abstract expressionist, saw no war images. In the late 1960s, the Vietnam War returned him abruptly to figurative approaches using a gritty, almost cartoon-like style. He apparently felt that the world no longer deserved art of
beauty and tranquillity.