When applying for U.S. citizenship, in the N-400 Application for Naturalization Form (mirror), in the travel history section, one has to indicate trips abroad longer than 24 hours. Can many trips abroad below 24h cause any issues on an N-400 Application for Naturalization Form or during the subsequent naturalization interview, or one should just ignore them, regardless of how many they are?
Trips of 24 hours' duration or shorter do not count at all when determining presence in the United States for the purpose of naturalization, because
USCIS will count the day that an applicant departs from the United States and the day he or she returns as days of physical presence within the United States for naturalization purposes.
Any trip of 24 hours' duration or less will necessarily imply a return to the US on the same calendar day as departure or on the following day, resulting in no period of absence being counted.
To put it another way, days of absence are counted only if the immigrant is absent from the US for the entire calendar day, from midnight to midnight. If the immigrant returns within 24 hours of departure, there are no such days.