The Three-Day War was a conflict between the USSR and NATO forces in Europe following Impact Day. Although it is unknown why the USSR declared war initially, it was probably to claim whatever land they could following the chaos of Impact Day. The conflict was mostly small scale, with an estimated 17,000 casualties.
Opening Attack (July 9th, 1961)
The first attack occurred on July 9th, 1961, and was supposed to be a pre-emptive strike against NATO and the rest of Western Europe. Eight Soviet divisions crossed the East German-West German border, intending to take Munich as fast as possible. With only five NATO divisions available for defense, within several hours, it looks like the Soviets will stage a breakout, having already advanced several miles into West Germany. However, NATO still had one non-nuclear last ditch defense attempt. Almost 250 planes were diverted from other sections of the border and ordered to stage an air assault on the advancing Soviet forces. This assault forces the Soviets to temporarily halt the offensive, allowing NATO to reinforce.
Second Day (July 10th, 1961)
This day represented NATO's attempt at a counterattack. Using seven divisions with heavy air support, they attempt to push the Soviets back. Five divisions are sent in a head-on attack, with the other two attempting a flanking maneuver. Despite initial success for NATO, The USSR called up two more reserve divisions to combat NATO's flanking maneuver. As a result, NATO's plan to push the Soviets back failed, but they still had superior air coverage, allowing them to push back the battle lines to nearly pre-war borders. At that point, the Soviets stage a defense, which stops any further attacks from NATO.
Final Day (July 11th, 1961)
The Soviet line continues to hold, but it is forced back to only about a quarter of a mile away from pre-war borders. With the war already unpopular among Soviet officials, and even less popular among the general public. Continued NATO attacks make it nearly impossible for the USSR to even hold its gains, let alone take more land. The war seems to be going nowhere for ether side.
Resolution of the Conflict
In the end, the conflict is basically a white peace. Although the border does change slightly in the favor of the Soviets, it is only a few hundred meters in, totaling less than three sq mi. The war was widely considered pointless, and a waste of resources that could have been used in other ways.