defend national security

• 维护国家安全

defend national security的用法和样例：

例句

1. We made practical efforts to safeguard state security.
   我们切实维护国家安全。
2. Nonetheless, to uphold state security, China, like many countries in the world, has also imposed some proper restrictions.
   但是，为了维护国家安全，中国，和世界上的很多国家一样，也有某种限制。