Starcraft2 definitely needs long term planning. It may not look like that to an outsider because a good caster decomposes that into actions, consequences and re

Starcraft2 definitely needs long term planning. It may not look like that to an outsider because a good caster decomposes that into actions, consequences and reactions. But to be able to play competitively you need a long term plan. The momentary triggers you mention are the distilled knowledge of long term planning and experience. A player executing a baneling rush is a long term plan. Then that player scouting the opposing terran player building a bunker and two barracks to defend can make him to decide to double expand instead of going forward with his baneling attack. This may seem re-active but in truth those decisions depend on long term planning. Pro players can make this long term planning calculations quite fast, the decisions may even appear re-active, however they are based on the long term calculation of the most probable path to victory.