President Trump is definitely not happy with many NATO leaders, and when he attacks NATO countries, so many officials don’t seem to know what to do.
The Donald is acting like someone who is aware that folks laughed at him behind his back during the difficult 2016 campaign.
NATO leaders might try finding out if that was the case, and making amends where necessary if the alliance is of any importance to them.
You might say you’ll just wait Trump out, but 8 years is a very long time. A lot can happen. Anger might just need to be pacified.