'cornerstone of security' is a correct and usable phrase in written English.
It is often used to refer to something that provides a foundation or basis of security, such as a law, policy, or system. Example: The new cybersecurity policy is seen as the cornerstone of security for our organization.
The Russians seem to regard the A.B.M. as the cornerstone of security.
Its peace with Israel is the cornerstone of security for the Jewish state and any future resolution of the conflict with Palestinians.
The centre-left must promulgate its own vision of a cohesive society, backed by a concept of sovereignty that recognises the nation-state as the cornerstone of security and belonging.
MOSCOW — Russia's president, Dmitri A. Medvedev, on Friday called the New Start treaty "a cornerstone of security for the coming decades," and spoke warmly of President Obama, saying that "under very difficult circumstances, he managed to make the Senate ratify this document".
Earlier in the day, Biden told reporters in Tokyo that the US-Japanese security arrangement was "the cornerstone of security not merely in the Pacific basic but the cornerstone upon which our security is built for the next 20 years or more".
"Trump's thinking represents a completely new approach to collective security and the system of alliances that have been the cornerstone of our security system.
The transatlantic alliance, the cornerstone of western security since 1945, looks in deep trouble.
We see this as helping to solidify a relationship that we want to remain the cornerstone of our security strategy.
And whatever its failings, most of NATO's members still see it as the cornerstone of their security and the irreplaceable bond that joins America to Europe.
As he did on previous stops in Britain and France, the president described the trans-Atlantic alliance as the cornerstone of American security.
Despite such hand-wringing among Japan experts in the United States, Mr. Hatoyama continues to emphasize that the alliance with Washington remains the cornerstone of Japanese security.
