Your question addresses the issues of both tragedy and modernity in O'Neill's drama. First, are we certain that Long Day's Journey into Night satisfies the definition of tragedy? In my view it does, because it fulfills the Aristotelian requirement of evoking pity and terror. The Tyrone family is hugely dysfunctional,...
Your question addresses the issues of both tragedy and modernity in O'Neill's drama. First, are we certain that Long Day's Journey into Night satisfies the definition of tragedy? In my view it does, because it fulfills the Aristotelian requirement of evoking pity and terror. The Tyrone family is hugely dysfunctional, and the single day in its history that O'Neill gives us is almost unbearably sad. Each family member is trapped in his or her own sense of guilt and failure. Tyrone is a has-been actor who, though having achieved great fame and wealth, still senses that his artistic achievements have been inadequate. His sons are massive disappointments to him. Jamie is an alcoholic ne'er do well. Edmund has potential but is consumed by self-pity and is physically ill with consumption (tuberculosis). Until the end of the play all are in denial about his illness, partly because all (except perhaps Jamie ironically) consider consumption a death sentence. Mary has retreated into a dreamworld because she can't bear the stress of living within this family, and she uses narcotics as a coping mechanism, trying unsuccessfully to hide this from her husband and sons. All the Tyrones are mired in substance abuse—either alcohol or drugs—as a means of self-medicating.
The one element lacking is a genuine "tragic ending." In fact, the ending is ambiguous in that we don't know what will eventually become of Edmund and the others. The climax is his announcement to his mother that he has consumption, but we're left to wonder what the consequences of it will be for him. The real-life Edmund—Eugene O'Neill himself—recovered from the illness. But the ending shows the family still submerged in hopelessness, with Tyrone saying "Pass me that bottle," continuing to drown himself in liquor because he sees no way out for the wreckage his family has become.
The play is "modern" in the sense that it is a "middle-class" drama in which a domestic dynamic is laid bare and honestly examined, following in the direct line of nineteenth-century dramas by the European playwrights Hebbel, Ibsen, Strindberg and others. But the substance-abuse theme is especially contemporary and even shocking in the manner in which it is portrayed. Altogether, as with O'Neill's work as a whole, the play was a seminal achievement in modern drama.