Following the incident regarding the problems caused by the Blue Sea Empire being resolved without any real problems for the Star Shattering Sect, Elder Song didn't dare let his guard down. Understanding that this was unlikely to be the only retaliation from the Blue Sea Empire now that they had fallen out with them according to what he had learnt about from Xuan Hao.
At the very least, it was clear from the first retaliatory response that the Blue Sea Empire wasn't looking to start an outright war with the Star Shattering Sect or try to fight them to the death. At most attempting to use their power as the local hegemon to limit the influence of the sect to the best of their abilities.