Answer:
The British believed the League of Nations could not succeed without the United States.
Step-by-step explanation:
The cartoon shows a made of stones labeled with members of the League of Nations. Missing from the center of the bridge is the keystone labeled "United States." A keystone is a special stone set in the center of a bridge to keep it from collapsing. The cartoon implies that the British believed without the United States, the League of Nations is likely to fail.