I’ve been over this before, but it bears repeating in light of President Trump’s (R) and SecState Marco Rubio’s contemplating the US leaving NATO altogether. The misperception is this:

The alliance’s lifeblood is its deterrent credibility: the perception by potential adversaries that attacking a NATO member would likely trigger a war with the full alliance, including the US.

As the news writer noted a bit later in his paragraph, though, this is a chimera, one that I claim is dangerous by its existence.

The alliance’s political promise to defend its members goes beyond the flexible wording of its famous Article 5, which says that each country in NATO would help a member that is attacked by taking “such action as it deems necessary.”

The relevant part of Article V is this:

The Parties agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all and consequently they agree that, if such an armed attack occurs, each of them, in exercise of the right of individual or collective self-defence…will assist the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.

“Such action” includes—but does not require—a military response.

Congress passed, in 2023 under the Biden administration, a law requiring a two-thirds vote of the Senate agreeing before the US could withdraw from NATO. The law has questionable constitutionality, interfering as it does with the President’s constitutional Article II role as our nation’s Chief Executive and our military’s Commander-in-Chief. This question is easily sidestepped, though, simply by adhering to the flexible wording of the NATO treaty’s Article V and declining to commit American military to a fight, confining our response, instead, to diplomatic words of demurral regarding an attack on other members.