What policy is most clearly supported by Kennan’s analysis in the excerpt?

In my view, the Soviet Union is driven by a deep-seated ideology that seeks expansion and global influence. I contend that the Kremlin’s actions are the product of a belief in its inevitable victory in the contest of ideas. During my analysis, I observed that a lack of internal accountability within the communist system enables unchecked expansionist aspirations. It becomes evident that a strategy aimed at containing this influence is not merely reactive but a deliberate effort to expose its inherent contradictions. Consequently, a steady, vigilant policy to limit Soviet expansion emerges as both necessary and prudent. Such an approach, based on containment, will encourage internal reform and fortify democratic institutions. — George F. Kennan, ‘The Sources of Soviet Conduct’, July 1947