"He could not unbuild it now"

The role he had effortlessly assumed and unconsciously learned, he was still playing and would play. . . . How easy it was to be a patriot who had avenged his country's wrongs by spectacular assassination. How hard it had always been to be himself! This role was so easy. It asked so ridiculously little of him--just to lie here until the time came to cross the river, just to keep from walking around on his broken ankle, just to escape. . . .
     The role, however, was growing harder to play. Almost as hard, if one faced it squarely and took everything into consideration, as it might have been to go ahead and play himself, a handsome young actor full of unnatural love and hatred, with a soul in torment and a lost voice. If it got much harder he might have to give up the part altogether. But no, he could not do that, could he? He had to keep on with it, because, terrifyingly, assassin and self were now one and indissoluble. He brought his right hand up close to his face and looked at it. That reverberating death of Lincoln, that enormity, that amplest structure in America--he could not unbuild it now. With this hand, it was built forever and nobody could push it down. He hid his hand in the water over the boat's side, but not to cool it for it was cold as death.
     --From The Spur