how did gulliver succeed in preventing an invasion on lilliput?

Chapter V

"The Author by an extraordinary Stratagem prevents an Invasion. A high Title of Honour is conferred upon him. Embassadors arrive from the Emperor of Blefuscu, and sue for Peace. The Empress's Apartment on fire by an Accident; the Author instrumental in saving the rest of the Palace."

When the Lilliputians and Blefuscudians go to war, Gulliver proves to be very useful by dragging the entire Blefuscudian fleet of ships to the shore of Lilliput, where "The Emperor and his whole Court stood on the Shore expecting the Issue of the great Adventure." When Gulliver arrives, he cries out, "Long live the most puissant Emperor of Lilliput!" The emperor gives Gulliver the land's highest honor, "Nardac."

Later the emperor requests that Gulliver go back to the enemy's shores and do his best to destroy what is left, turning the empire into a province. Gulliver thinks that this action is going too far and declines the request. Three weeks after Gulliver's victory, an embassy from Blefuscu arrives offering peace, which the emperor accepts.