His instructions directed him to sail for Boston should his fleet meet with any disaster, or should a superior British fleet appear on the coast.
This communication threw Sullivan and his army into despair.

General Greene and the Marquis de Lafayette were directed to wait on the Admiral with a letter from Sullivan remonstrating against this resolution, and to use their utmost endeavors to induce him to change it.
They represented to him the certainty of carrying the garrison if he would co-operate with them only two days, urged the impolicy of exposing the fleet at sea, in its present condition, represented the port of Boston as equally insecure with that of Newport, and added that the expedition had been undertaken on condition that the French fleet and army should co-operate with them; that confiding in this co-operation, they had brought stores into the island to a great amount, and that to abandon the enterprise in the present state of things, would be a reproach and disgrace to their arms.

To be deserted at such a critical moment would have a pernicious influence on the minds of the American people, and would furnish their domestic foes, as well as the common enemy, with the means of animadverting severely on their prospects from an alliance with those who could abandon them under circumstances such as the present.

They concluded with wishing that the utmost harmony and confidence might subsist between the two nations, and especially between their officers; and entreated the Admiral, if any personal indiscretions had appeared in conducting the expedition, not to permit them to prejudice the common cause.
Whatever impression these observations may have made on the Count, they could not change the determination he had formed.
General Greene, in his representation of this conversation, stated that the principal officers on board the fleet were the enemies of D'Estaing.

He was properly a land officer, and they were dissatisfied with his appointment in the navy.