Why did the timing of concessions matter to a summit?

Was Japan's insistence on a summit comparable to North Korea wanting direct talks with the United States?

There is a limited comparison. The difficulty identified is the timing of concessions and what conceding before talks would mean in each country's domestic politics.

A viewer compares Japan's insistence on a summit with North Korean demands for direct talks with the United States. The comparison turns on whether concessions should precede negotiations or remain available as bargaining terms at the meeting. A comparison with the Washington Naval Conference argues that advance cuts could become a ceiling on further concessions when one side had expected them to be an opening offer. In the interpretation of 1941 offered here, Japanese concessions before a summit would make the government appear publicly defeated, while American domestic pressures encouraged demands for those concessions as a condition of talks. The explanation attributes the impasse to incompatible political constraints and a misreading of those constraints; it rejects the inference of a deliberate American decision to produce war.