Dr Manhattan's unusual hyperconsciousness allows him to perceive time in multiple facets. He slides through time and has a keen sense of predestination. For him, all time is simultaneous; all things happen at once. Therefore, he knows what "will" happen in "the future" but is incapable of doing anything about it. An obviously complex, distant, otherworldly character, Manhattan is ageless and indestructible but poignantly paradoxical in his fatalistic yet omnipotent existence.
Some even claim that Dr Manhattan might even be an indirect allegorical reference to Vishnu / Krishna.
Dr Manhattan appears to transcend space / time, talks metaphysically about reality, life and death. Dr. Manhattan seems beyond human, beyond super-hero, evolving god-like. He has a blue hue around him like Vishnu/Krishna.
Of course that in itself, doest mean anything, however lets roll back 60-years to the time of the first test of the Atomic Bomb.
In July 16th 1945, the Manhattan project, conducted the first atomic bomb tests, at Jornada del Muerto desert near the Trinity site in the White Sands Missile Range. Supervising scientist Robert Oppenheimer (a big believer of the Vedas/Upanishads) quoted Vishnu / Krishna from the Bhagavad Gita - "I am become death - the destroyer of worlds", just as the first Atomic bomb was detonated.
Afterwards, he recalls: "We knew the world would not be the same, few people laughed, few people cried, most people were silent. I remembered the line from the Hindu scriptures, the Bhagavad Gita. Vishnu is trying to persuade the prince that he should do his duty and to impress him he takes on his multi-arm form and says - 'now i am become death, the destroyer of worlds.' -- i suppose we all thought that one way or another." - J. Robert Oppenheimer