HONG KONG — When a draft of China’s new national security law was made public in May, critics argued that it was too broad and left much open to interpretation.

In the final form of the law, which the government said Wednesday had been enacted, Beijing got more specific, but in a way that is sending ripples through the global technology industry.

New language in the rules calls for a “national security review” of the technology industry — including networking and other products and services — and foreign investment. The law also calls for technology that supports crucial sectors to be “secure and controllable,” a catchphrase that multinationals and industry groups say could be used to force companies to build so-called back doors — which allow third-party access to systems — provide encryption keys or even hand over source code.

As with many Chinese laws, the language is vague enough to make it unclear how the law will be enforced, but it suggests a new front in the wider clash between China and the United States over online security and technology policy.