We're starting the mission by finding that moron Haggard... deal with the enemies at the gate (red barrels located here should be quite useful here).
Search the building located next to the gate. You'll find here the MRTR-5 device. Take it, as it may become useful in the next part of the mission.
You'll meet quite heavy resistance here (infantry with rocket launchers and a heavy tank), so precise aiming and frequent artillery strikes will be essential here. You can also use the stationary rocket launcher to eliminate that tank.
Once You destroy it, get to the bridge, but don't enter it. Use the artillery to destroy the camp on the other side of the river.
If You jump into the water and approach the camp from the left, You'll avoid enemy fire (including the one from the bunker). Clear the buildings located here and deal with the guy inside the bunker.
Now go to Haggard (red smoke). Your next target is the antenna located on the hilltop. This place is crawling with snipers, so try to run to the first enemy You see, kill him and take his rifle. A new weapon will allow You to clear the rest of the hill. And don't forget about the artillery strikes - You can still request them.
On the hilltop, You'll find a building, with a C4 inside. Use the charges or the artillery to blow up the antenna box.
Now move forward. Use the sniper rifle to get rid of incoming enemies. After a long march You'll see the next antenna. Kill all the infantry defending it. When You secure the terrain, destroy the antenna box with an artillery strike.
An enemy chopper will come here soon. You'll find an RPG next to the antenna. Take it and use it to destroy the helicopter. It's not easy, but still possible. When You turn him into scrap metal, go to the third antenna. However, remember You're still on enemy's soil - expect snipers and soldiers with assault rifles.
Once You get through the fields, You should see the antenna and a few buildings. Get Yourself an assault rifle. And don't forget about attacking the enemy base with artillery, in order to eliminate its personnel.
There's a possibility You'll be attacked from behind by an enemy vehicle. Hit it with the artillery too.
Once You secure the base, search the guard tower standing near the antenna. You'll find there some C4 - Use it to blow up the antenna box. Better don't use the artillery here - we don't want to damage the heavy tank that Russians are willing to lend us :)
Hint: there's an AA gun located next to the antenna. Use it to destroy the trees nearby (Manic Lumberjack achievement).
After the explosion, exchange the C4 for a Power Tool, it lays next to the tank. Go regroup with Your buddies.
Now get inside the tank and follow the gold! Go to the harbor marked on the map. I advise You to change the view - Your shots will be more accurate.