I was long aware that we planned to do this kind of thing all across Soviet-occupied eastern Europe and in West Germany as Soviet armor plunged west:
In the event of World War III – with Soviet forces expected to come pouring across the Berlin Wall – members of the detachment, who never numbered more than 100 men, were expected to blend into the city and make life difficult for the much larger Communist force.
Teams were assigned sabotage missions, ready to destroy key transportation lines, military equipment and other targets. They also would be expected to train and lead guerrilla forces that would then be tasked with harassing the Soviet troops from behind enemy lines, buying important time to allow NATO forces to mount a counterattack.
This is the sort of thing we and our new NATO allies under revived threat from Russia should be planning to do now.
On the bright side, we will have more options to support such stay-behind forces with better communications to provide conventional fire support. I especially see options from the Baltic Sea for NATO until NATO heavy forces drive the Russians back.
UPDATE: And as I note in this post on a war in the Baltic states, we do practice for it.