What was the pincer strategy?

Answer 1

Many terms have been used historically, Chaka Zulu called it the horns and the bull, the modern term would be an envelopment. In the open a double envelopment like the "horns and the bull" is required. When a flank is covered by impassible terrain like a sea, marsh or mountain range, it can be used as one of the "horns" and you have a "single" envelopment. With the advent of the helicopter, the Marine Corps developed the "Vertical Envelopment" by inserting a force at a point of their choice to the left, right or rear of the beach head. Airborne forces were also employed in the same manner, that is, to insert a horn point where and when it ws considered effective.