- There is nothing automatic about Article V. Yes, it has meant that an attack on one is seen as an attack on all BUT it requires a decision at NATO HQ among the permanent representatives from the members. That decision is not a vote but one by consensus. And getting consensus might just be really hard for reasons I elaborate below.
- If Article V is involved by NATO, no member will be obligated to do anything specific as "each country will respond as they deem necessary." Yes, there is an opt out clause in Article V because the US insisted long ago AND it is hard to get consensus if countries have to surrender all decision-making after that.
- Oh, and NATO is a defensive alliance. So, at least a few countries would not be so thrilled to join an adventure the Americans started.
Moreover, rather than investing in good will with American assurances of support in case Europeans need it, Trump has been threatening the allies about mythical back payments and reaching a standard now that was semi-agreed to for 2024--2% of GDP spent on defense. So, that also does not create a lot of support for what would be seen as a replay of 2003.
Which gets to the heart of the matter: NATO members have their own domestic politics. To support the US in this effort would require not just looking at the polls, but, if things got serious, votes in parliaments because nearly all European countries require votes to deploy troops. And with mostly coalition governments, those votes are hardly guaranteed. Given that Trump is unpopular in most European countries, it would be very, very hard to get NATO members to agree to expend serious money and risk the lives of their troops especially for an administration that is not seen as particularly competent.
One last thing: with the strike on Suleimani without notifying anyone, Trump has endangered NATO troops on the ground in Iraq. That is something that will weigh heavily in much decision-making in the capitals of NATO members.
Update: One more thing: threatening to commit war crimes (hitting cultural sites) is a great way to ensure that the Europeans do not join in. Most of these countries are very sensitive to these kinds of issues, and will not want to be present where war crimes are being committed. So, Trump is making it much harder for any European leader, if they wanted to, to try to join any US-led effort.
There will be meetings, because that is what NATO does. But don't expect any policy statements anytime soon. The members are all waiting to see how things develop.