Tyrants of Time

Do dictators rise to power by accident? What if their ascendency is planned throughout history by men of the future who play with time as if it were a toy. And what if 1955 is their key year....
Something buzzed in Tedor Barwan's right ear, driving the throbbing hum of the Eradrome momentarily away. In the sea of sound the rasp of the radio receiver buried in Tedor's mastoid bone was still unmistakable, and it alarmed him. He tongued the transmitter in his palate and said, This is Barwan. Go ahead.
There was nothing but the noise of the Eradrome, the shouts of the hawkers of a dozen centuries, the constant droning of the tourists garbed in costumes of fifty generations, the couriers noisily arranging guided family tours, the school teachers shepherding their squealing charges primly but still unable to hide their own eagerness. Tedor repeated, Go ahead. Go ahead! He'd dialed for a closed connection between himself and Fornswitthe previously; thus it was Fornswitthe who had tried to contact him.
Why?
Tedor—help! The voice hissed in his ear once, then was silent. It was Fornswitthe, all right. Silent now.
Tedor took long strides toward the slidefloor. The Eradrome was so crowded that he couldn't break into a run. He was bone-weary from too much work and had come to the Eradrome for a few hours of relaxation, leaving Fornswitthe alone to start their report on the 20th century. The report was dynamite.
Tedor jostled his way along on the slidefloor, not content with its slow pace. The great green-tinted bubble of the Eradrome soared five hundred feet into the air and burrowed twice that depth into the ground. Tedor was on one of the lower levels and knew it would take some time before he could reach the surface level.
Busman's holiday, Barwan?
Tedor whirled sharply before boarding the next ramp. He recognized the plump, thick-jowled face but could not tag it with a name.
Something like that, Tedor admitted and kept walking.