How does Tom Clancy use imagery in Debt of Honor?

Example of Imagery:

Goto's voice grew louder. For the first time his fist slammed down on the podium, and the crowd responded with a roar. His diction became more rapid. The crowd was moving inward, and Clark watched the speaker's eyes notice it, welcome it. He wasn't smiling now, but his eyes swept the sea of faces, left and right, fixing occasionally in a single place, probably catching an individual, reading him for reactions, then passing to another to see if he was having the same effect on everyone. He had to be satisfied by what he saw. There was confidence in the voice now. He had them, had them all. By adjusting his speaking pace he could see their breathing change, see their eyes go wide. Clark lowered the camera to scan the crowd and saw the collective movement, the responses to the speaker's words.