Conflict is composed of an action and reaction struggle between the protagonist and the antagonist, with each action and each reaction taking place on a higher level of intensity, creating escalation. The struggle is also responsible for the uncertainty of the ultimate outcome, and uncertainty creates tension. Because struggle is comprised of reversals, no matter how bad things seem to get for the protagonist, hope remains that he will yet prevail, and the presence of hope maintains the uncertainty of the ultimate outcome. Without the possibility of reversals, once the antagonist would appear to triumph, hope would be lost for the protagonist and the story would be over. As long as the protagonist has a hope of reversing the triumphs of the antagonist, and as long as the antagonist can do the same to the protagonist's victories, there is uncertainty and tension. Uncertainty must be maintained as long as logically possible otherwise there will be no tension and the reader will lose interest. Tension rises as the struggle escalates but the outcome remains uncertain. Conflict is responsible for escalation of the action as well as for uncertainty and tension. Conflict also creates suspense.
Conflict is caused by some event that suggests a possible disaster. In order to avoid the disaster, the protagonist acts, and comes in conflict with forces that wish to make the disaster happen. The ultimate outcome, however, because of the conflict, is uncertain or suspended. As long as the outcome is uncertain, suspense is maintained. As long as the conflict is unresolved, its outcome remains suspended.