I assume the Polish attack on Russian or Belarusian forces would come in reaction to a Russian or Belarusian attack, in which case NATO should already have come to the aid of Poland. Things can get muddled in the light of the alternative ways of "waging war" which Belarus seems to be engaged in - e.g. inviting thousands of migrants with promises of an easy passage into the EU, providing them with simple armaments [1] and positioning them on the Polish border with no way of retreat back in to Belarus - which has led to both NATO as well as Russian forces to converge on the scene [2], a situation in which the question of "who fired the first shot" is hard to answer.

[1] https://www.telegraph.co.uk/world-news/2021/11/16/belarus-ar...

[2] https://www.itv.com/news/2021-11-12/russia-sends-paratrooper...

In theory, sure.

But Ukraine is right on the border of Poland. And what we saw in Ukraine is by the time Paris, London and Berlin notice something is amiss, Russia has already achieved their goals. And the fear-of-triggering-WW3 goes both ways.

I can believe Poland would want to be well equipped, so they can hold out for a few days so their allies have time to mobilise.

NATO is a defense alliance. If RF will directly attack a NATO country, then a nuclear war will begin. When a NATO country attacks another country, NATO will not be involved.

EDIT: I'm wrong about Afghanistan.

>For example: USA war against Afghanistan.

The US successfully invoked NATO article 5 after 9/11 requiring all NATO members to assist militarily.

This is either satire or the worst possible example, since the war in Afghanistan is the only time in history article 5 has been used.