Threats to American national security come from three sources: major powers, malevolent states, and weak or failed states. There is, obviously, nothing new about tension with another major power, with the most obvious current challenge coming from China.
The other two sources of threat to American national security—malevolent states with effective national control but limited aggregate material capabilities and states that cannot control their own territory (failed or weak states)—are historically unique. Threats from both of these sources are the result of the decoupling of underlying material capability (as indicated by GDP, population, military spending, and technological capacity) and the ability to inflict harm especially with nuclear and biological weapons.
In the case of malevolent states these capabilities are controlled by the state apparatus. Although the ability of malevolent but under-resourced states to inflict catastrophic damage is new, the measures to counter these threats are not. They include offensive, defensive and deterrent military actions, as well as economic sanctions.