Pinning this comment to address people's questions and worry around article 5 being invoked in light of the 2 killed in the Polish border town.
This is NOT the start of WW3, folks. Calm. However, Poland has a lot of options to make things incredibly unpleasant for Russia without kicking off WW3.
The situation is still developing and I will update this comment as confirmed information comes in.
The current most credible theory is:
US official have told POLITICO it was likely caused by a missile strike or errant missile, not remnants of a missile Ukrainian armed forces shot down. twitter.com/laraseligman/status/1592615331826405377
Russia missiles did hit electrical infrastructure near Kovel, 50kms from the Polish border. twitter.com/Liveuamap/status/1592609073090138113
Ukraine confirmed earlier today 73 missiles (out of 90) and 11 drones were shot down. twitter.com/TpyxaNews/status/1592574510989185024?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1592574510989185024%7Ctwgr%5E1772ae31a5e3d7e2f8b2f60b78ef8c20d19f1259%7Ctwcon%5Es1_&ref_url=https%3A%2F%2Fwww.redditmedia.com%2Fmediaembed%2Fliveupdate%2F18hnzysb1elcs%2FLiveUpdate_7477350a-650d-11ed-a4c7-76d0d5734e49%2F0
A quick refresh on NATO bylaws:
Article 5: An attack on one member of NATO is an attack on all of its members.
Article 4: The Parties will consult together whenever, in the opinion of any of them, the territorial integrity, political independence or security of any of the Parties is threatened.
Here's everything you wanted to know about NATO Article 4 but were afraid to ask. scholarlycommons.law.emory.edu/cgi/viewcontent.cgi?article=1224&context=eilr