The famous four-stack destroyers do not yet exist

Could the United States rely on its large Wickes- and Clemson-class destroyer flotillas in a war beginning in 1914 or 1915?

No. Those mass-production classes were not laid down until 1917 and 1918, leaving the prewar fleet dependent on much smaller batches of earlier destroyers.

American industrial potential must be separated from ships actually available in 1914 and 1915. The numerous Wickes and Clemson-class four-stack destroyers belong to the 1917-18 mobilization, with their keels laid years after this counterfactual war would begin. Earlier classes were built in small batches, leaving the fleet with far fewer destroyers than its later reputation suggests. Plans and latent industrial capacity could not immediately substitute for the infrastructure and completed hulls needed at the opening of war. The United States had considerable future potential, though much of it was not yet usable in 1914 or 1915.