Excerpts of the President's News Conference
I don't know of any change in the attitude of the United States Government in relation to submarines from the position that was taken at the time of the Washington Conference. I don't want to say that the United States Government wouldn't be willing to change the policy that it announced at that time, but the policy then announced is the policy that we have at the present time, a limitation of submarines, with an open mind to hear and consider any other suggestions that might be made in relation to the use or abolition of submarines.
Source: "The Talkative President: The Off-the-Record Press Conferences of Calvin Coolidge". eds. Howard H. Quint & Robert H. Ferrell. The University Massachusetts Press. 1964.
Calvin Coolidge, Excerpts of the President's News Conference Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/349126