Crisis bargaining literature has predominantly used formal and
qualitative methods to debate the relative efficacy of actions,
public words, and private words. These approaches have overlooked
the reality that policymakers are bombarded with information and
struggle to adduce actual signals from endless noise. Material
actions are therefore more effective than any diplomatic
communication in shaping elites’ perceptions. Moreover, while
ostensibly “costless,” private messages provide a more precise
communication channel than public and “costly” pronouncements. Over
18,000 declassified documents from the Berlin Crisis of 1958–63
reflecting private statements, public statements, and White House
evaluations of Soviet resolve are digitized and processed using
statistical learning techniques to assess these claims. The results
indicate that material actions have greater influence on the White
House than either public or private statements; that public
statements are noisier than private statements; and that private
statements have a larger effect on evaluations of resolve than
public statements.