In theory yes, practically speaking it is not necessarily as clear cut as one attack means everyone jumps in. Putin loves that gray zone of using domestic agents in other countries or deniable situations like wayward drones and also low stakes. Keeping the stakes low in such incursions keeps the wider NATO alliance from jumping in like they would for a clear cut all out invasion, but still allows for antagonizing countries and making NATO look weak because they can gradually push the envelope so long as they managed to stay on this side of the moving line. For example, they bombed an apartment complex with a drone in Romania recently and went teehee we didn’t mean that. The assembled NATO countries agreed with them because it’s not considered worth declaring war on Russia over a partially damaged apartment complex, particularly since no one actually died. Similarly a Russian missile blasted a field in Poland but while technically an attack on Polish soil people will not respect going to war over a disruption of just literal Polish soil. If Russia pushes just slightly and slightly harder over time then at any particular step it can seem pretty unreasonable to upend the table and go to war with a nuclear power over something that is just a twinge worse than what you accepted a month ago. That can sow dissension in the alliance on how to respond. And since Lithuania is quite weak on its own, it’s very reassuring to Lithuania to have states with more oomph invested in their defense.

All the ongoing stuff above and the intelligenece recieved are in the backdrop of the ongoing war with Ukraine anyway so we know that that whole endeavor is evidently still not enough for Putin to give up on gray zone shenanigans. It seems unlikely that one tank brigade would make the difference when each side has somewhere around a million people slugging it out right now.