Exactly. It seems that alphabet development is closely related to the regions more focused on international trading (the region we know as Phoenicia) rather than war and conquest of the neighbours. Maybe a system that represent sounds was useful to write words from sounds in multiple languages that were never heard before, unlike pictograms, hieroglyphs or cuneiform, that had to be adapted to each language.
But also, Phoenicians did not develop the alphabet. The basic notion of encoding sounds with glyphs is a Egyptian invention, and the earliest evidence for true abjads (from which Phoenician script and other Semitic writing systems all derive) is also from that same area.
Note that war and conquest of neighbors means managing (in particular, taxing) a large foreign-speaking population, whereby abjads and alphabets also come in handy. Not to mention the monuments - if you are a king erecting, say, a monumental stele to boast about having vanquished a mighty foreign ruler, it might behoove you to spell his name in a way that is sufficiently recognizable for people to appreciate the achievement.