Clash of Steel - How do the missions work? Missions explained!

About Clash Of Steel: Operation Unthinkable – American vs Soviet Complete Starter Set, from BoardGameGeek:

Welcome to Clash of Steel. It's 1948 and the war has started again. Based on an Alternative History where the war in Europe finishes in 1944 with the surrender of Germany, but restarts just four years later in the face of Soviet aggression. Players take to the tabletop with one of four initial nations in Epic Tank-On-Tank Combat using Highly Detailed Multi-part Plastic Miniatures, battling over objectives in an attempt to control the battlefield and defeat their enemies. Featuring Dynamic Mission Based Game Play to ensure that every battle is unique and cinematic. This Starter Set contains everything you need to get started, including rules, miniatures, dice, tokens and much more. This box set contains...21x Highly Detailed Plastic Model Tanks, 22x Tank Commanders, Decals, Complete Rulebook, Quick Start Rules, 20x Dice, 2x Force Booklets, 20x Unit Cards, 34x Tokens, 3x Objective Markers, 2x Victory Point Dials, 26x Tactics Cards, 6x Mission Setup Cards, 9x Mission Rule Cards, 22x Objective Cards How will you re-write the history books? -description from the publisher