There is nothing in the parent post to even hint that they are saying that the US is to blame for what happened.
The US cannot be trusted to fulfill it's approved upon role in NATO if and when the push comes to shove (that damage to the US reputation is done).
I want to make it clear that the US does not sholder this responsibility alone. Every signatory to the convention is required to come to it's allies need if needed.
Europe has to get it's act together when it comes to securing its own borders, with tech and armaments produced inside said borders but in a cooperation with the US. As partners.