question #1 Sahih al-Bukhari 4110, Book 64, Hadith 154 : What strategic shift in military tactics is indicated by the statement about attacking rather than being attacked?

When the clans were driven away, I heard the Prophet (ﷺ) saying, “From now onwards we will go to
attack them (i.e. the infidels) and they will not come to attack us, but we will go to them.”