Interesting info, Jim. Putin longs for the old days of the USSR and its world influence. I really think the current Russian aggression is just a reflection of him personally and long term it cannot last, financially. At issue is whether the United States has the will and leadership to make it impossible for the Russians to ever catch up. As of now that answer is clearly no.
For Rick, I think we had our day in the sun dealing with the Russians. Even when we weren't holding them we cost them time by trying to avoid us. That said, from everything I have read our technology from the old days wouldn't do the trick today. If it did I would take some TAD in Kef anyday! :)

When I was retiring from Raytheon we had a concept using existing sensors and towed sensors, that used bottom mounted, continuously radiating low freq transducers, and bi-static or muti-static processing to track undersea objects. The navy rejected it since it would also light up blue forces. Today's signal capture and retransmit stealth technology might negate even the best active SONAR directly, but event-driven multi-static passive may still be our best alternative to Russian surge deployment. Pretty old technology though... probably obsolete in the UUSV world of today.