Final answer:
Washington did not have accurate intelligence about the British force, but he recognized that New York City was a likely target. Despite preparations, the British were able to flank the Americans at the Jamaica Pass and drive them from their fortified positions.
Step-by-step explanation:
Washington did not have accurate intelligence about the nature and number of the British force, which made it difficult for him to prepare adequately for their attack. However, he did realize that New York City was a likely target for the British. In response, the Continental forces constructed forts and fortifications on Long Island and set up obstacles in the water to defend against the British Navy. Despite their preparations, the British were able to land their troops on Staten Island and, on August 22, move to Long Island. The Americans had well-fortified positions in most areas, but inexplicably, the Jamaica Pass was almost abandoned with only a token guard. This allowed the British to flank the American forces and catch them off guard.
Washington's retreat from Long Island was remarkable, but the British had still driven the Americans from their fortified positions. Although the British missed a chance to capture Washington and end the war, their victory boosted their confidence.