Soap and Roach recover a lost ACS module from a downed satellite in Kazakhstan, Shepherd recruits Private First Class Joseph Allen to Task Force 141, then sends him on an undercover CIA mission in Russia in order to get closer to Makarov, so they kill a bunch of civilians in an airport and Makarov along with his posse speak in english so this is a dead giveaway, he obviously knows Allen is American. When they're done, Makarov kills Allen and leaves him there for Russian police to identify him as an American. So the Russians think it was a planned American terrorist attack and they invade the US, you can compare this to poop hitting a fan. The ACS Module that was recovered in Kazakhstan was already cracked so it allowed the Russians to damage America's early warning systems leaving them open for an attack. They chase Makarov around Russia and they go to find a prisoner in a Russian gulag, who is also the guy Makrarov hates the most, it turns out to be Captain Price, Price decides to help out but he goes nuts when he tries to stop a Russian nuclear launch so he fires a nuke at Washington DC and makes sure it detonates in the upper atmosphere, as a result it destroys the internation space station and the EMP blast makes everything fall out of the sky, suddenly it's raining aircraft and non of your electronics work, the air force assumes Washington DC was taken out but that wasn't the case so they used green flares on the roof so they prove the Russians didn't take over and so the airforce wouldn't bomb them, yay for them. So they narrow down Makarov's location, Price and Soap go to the aircraft boneyards in Afghanistan, Roach and Ghost go to raid Makarov's safehouse in the Caucasus Mountains. Roach recovers info that proves Makarov was responsible for the airport massacre, Shepherd then betrays and kills Roach and Ghost and burns them because he wants to be a war hero and he's just mean. Soap and Price find out and Nikolai comes to save them in his magical plane, you chase down Shepherd then chase him more on a boat, then you chase him in a helicopter but Price shoots down the helicopter so you're done chasing him then you go off a waterfall and you wake up at the shore where you chase down Shepherd again but he's staggering like a drunken hobo so no big deal, vatever. Soap tries to knife him ono he fails and Soap gets stabbed by Shepherd, as he is about to kill Soap, Price comes to save his bff Soap and starts fighting with Shepherd, Price gets pwnt but Soap pulls the knife out of his chest just in time to throw it at Shepherd's eye, killing him instantly. Soap and Price are wanted men so Nikolai comes to save them in his magical plane again. CONGRATS YOU NOW UNDERSTAND MODERN WARFARE 2'S CAMPAIGN!