Glory belongs to the party. What does it mean to have a cloak of bubble rain to strengthen national defense?

This is a poem written by Guo Moruo when he visited Putuo Mountain on the way to Zhoushan by the navy "Qingfengdian Ship" in June 1962. The original text is as follows: Hai Ping Huang, the hero lives in Wang Yang. Glory belongs to the party, and the cloak of bubble rain consolidates national defense.