NATO patrolling Baltic airspace

Last week NATO welcomed 7 new members, among which the 3 Baltic States. Since these countries don’t have fighter planes of their own, they asked the alliance to assist them. Today, 4 Belgian F-16s started to patrol the Russian-Lithuanian border.

Do you think this is still necessairy? I mean, the cold war is over, but I thought NATO and Russia were cooperating these days, but this new move seems to break up the relations between both.