what does the title ' all my sons ' mean?

The title of the play becomes clear in Keller's final line. After years of denial, he is forced to acknowledge that the soldiers who died as a direct result of his actions were someone's sons, and they all might as well have been his sons. But this line, with the title, actually serves two independent arguments that run through the work. "All My Sons" has both an emotional center and an intellectual center. The emotional "All My Sons" has the Keller family at its core, being primarily concerned with the impact of shameful secrets on family relationships, in particular how their past can come back to haunt the present. When the work is performed, audiences are usually struck the hardest by the story of the crime and its consequences for the Keller family.

But the intellectual "All My Sons" is the story of that same crime and its consequences not for the Keller family, but for the world. If Miller is proposing a world-scale ethic of concern for everyone's sons, he proposes that Keller (and each member of the audience) should find in himself a kind of generalized care for all of the sons and daughters in the world. Miller later wrote that he wanted the play to be about "unrelatedness," describing Keller as a man who "cannot admit that he, personally, has any viable connection with his world, his universe, or his society." The admission that the pilots were "all my sons" is, for Keller, an admission that he might as well have killed his own child. The admission is also a new understanding that it should not matter whether the dead pilots could have been his sons; rather, we all have an obligation to society to value everyone's sons as though they were our own. Whether that level of concern is possible or feasible, indeed whether it is healthy and desirable to refuse to help your own children and neighbors while you try to help the whole world, is a different question, but the idealist might give it a try.