"Strange Meeting" is one of Wilfred Owen's poems that illustrates the horror and futility of war. Owen fought in World War I and he quickly became horrified by the grim realities of war. In this poem, the speaker first notes that he has escaped the battlefield; he thinks this is some trench or tunnel dug out or bombed during a previous battle.
As his journey continues, he happens upon many "sleepers" who are all dead. The speaker wakes one of them up; the sleeper recognizes him and this is when the speaker knows he is in Hell; but this could indicate Hell itself or the figurative Hell of war. The speaker and the "sleeper" are both soldier-poets. Some critics note that this sleeper is the speaker's/Owen's alter-ego.
The speaker (perhaps still not aware that he is dead) is glad to be away from battle. But his alter-ego mourns the loss of his life because, had he lived, he would have used the opportunity to write more, to educate people about the futility of war, "I would have poured my spirit without stint." Since he, and people like him, have died, he fears that the world will go down a path of destruction, initiated by this "war to end all wars." He fears the world will be content with the destruction of this war and/or they will continue with others.
Now men will go content with what we spoiled,
Or, discontent, boil bloody, and be spilled.
In the last section of the poem, the alter-ego (sleeper) reveals that he is the one the speaker had killed. The alter-ego says, "I am the enemy you killed, my friend. / I knew you in this dark:" - The tragic/ironic implication is that the alter-ego knew him as a friend only in death. It took death for him to realize the futility of war. The alter-ego mourns the loss of his ability to share this truth in life, as he must accept his fate: "sleep."