At its heart, George R.R. Martin’s epic fantasy series, A Song of Ice And Fire — the inspiration for HBO’s excellent Game of Thrones — is a war story. Armies clash endlessly on Westeros, Martin’s continent of Seven Kingdoms. Legions of fans await the battles in Book Five, “A Dance With Dragons,” published on Tuesday.

The military strategy behind the gambits for the Iron Throne, though, is often MIA. Sure, you can marvel at cool swords named Ice or Oathkeeper, and read elegant descriptions of the destriers beneath their knights’ saddles. But it’s easier to understand which warriors will win in a duel than why Westerosi generals succeed or fail.

So the ASOIAF obsessives at Danger Room present the seven (natch) military lessons of Westeros. (Seriously, read no further if you’re not past “Game of Thrones.”) To understand who will win the Game of Thrones — and who will die — we need to identify what makes a great Westerosi commander. Spoiler: it has a lot in common with what makes a great commander back here in this boring, dragon-less world. Call the banners.

Secure Your Retreat.

Jaime reliably informs us that the deceased Prince Rhaegar Targaryen was a kick-ass knight. But he demonstrates how good soldiers can make bad generals. Rhaegar’s death at the Trident is an unforced error.

Check out the map of the Trident at Tower of the Hand.

Rhaegar marches north up the Kingsroad from King’s Landing to meet the rebel Robert Baratheon at the Trident, fingers of land sliced by rivers. But even though Rhae-Rhae has a clear path of retreat behind him, he either lets Robert’s forces flank him or he decides — with a dynasty on his shoulders! — to make a final stand. Either mistake is inexplicable.

But in Westeros, retreat is often a necessity. Ask Tywin Lannister or Stannis Baratheon. Maybe the Targaryen dynasty was doomed. But Rhaegar’s incompetence ensured it.

Lesson: Always retreat when you’re outmatched.

Robert Baratheon, Coalition-Builder.

As king, Robert is a drunken lout. Guys like that don’t tend to win wars. But while Martin emphasizes Robert’s inability to rule, hiding in plain sight is the reason he had a chance: Robert picks his allies well.

Look at the forces Robert aligned against the Targaryens when the rebellion gets underway: his main dude Ned Stark from the North. His mentor Jon Arryn and the knights of the Vale. His own Storm’s End crew, including his intense brother Stannis. To the center-west, the riverlands of House Tully. Before the war starts, House Targaryen loses everything but the south. Robert sews the whole deal up with the Lannisters by marrying Cersei, which ultimately doesn’t work out for him. But that’s how you set up a dynasty.

Lesson: Coalition warfare works.

Dragons: Westerosi Drones.

When you hear about new dragons, do whatever it takes to get them under your power. Euron “Crow’s Eye” Greyjoy, the psycho pirate, promises the Iron Islands he’ll use a magic horn to wrest control of Rhaegal, Drogon and Viserion from their mommy, Danerys Targaryen. As an insurance policy, he sends his brother Victarion to find Dany and form a (sexual) alliance between the dragon and the kraken.

Smart gamble. No one’s had any close air support since the last Targaryen dragons died, and it was the dragons that turned Aegon Targaryen into the Conqueror of Westeros. If either the horn or Viserion fail, Euron’s toast, but the weak Ironborn have no better option.

Lesson: Audacity in pursuing gamechanging military tech is no vice.

Doran Martell’s Strategic Patience.

Everyone dismisses gouty Prince Doran as a weakling. But no one wins more than Doran. He knows that there aren’t enough Dornishmen for a war with the Lannisters — who murdered his sister, niece and nephew — and if they fight, they’ll lose the awe of being an unconquered kingdom, the source of their deterrent. So while his brother the Red Viper dies in a vendetta, Doran locks up his bellicose nieces and thwarts his daughter’s reckless plan for war.

But Doran’s not backing down — he’s just not fighting the Lannisters until his son Quentyn hooks up with Danerys and her dragons. The Dornish are like the Iraqi Kurds of Westeros, ready for revenge once they sew up their big patron.

Lesson: Only an idiot launches a premature attack.

Thrones Aren’t Won By Navies.

The Navy vets here just spit out their coffee. In Westeros, though, woe to the sailors. Danerys becomes “Stormborn” when the storm accompanying her birth destroys the Targaryen fleet before it can cross the Narrow Sea. The Ironborn? Stannis out-admirals them and Robert proves they can’t fight on land once he lands on Pyke. Years later, Stannis sails through Blackwater Bay with a powerful navy — soon to be a flaming wreck thanks to a concealed chain Tyrion Lannister runs through the mouth of the bay, followed by a bath of wildfire.

Lesson: Ain’t nothing in the sea but the Drowned God.

Clear, Hold, Build.

Robb Stark is the Tommy Franks of Westeros. His army of Northmen feint and maneuver down the neck and into the riverlands, winning every single battle against the Lannisters. And then he loses everything. Why? Because he doesn’t ever consolidate his victories. The empty North is an easy target for the Ironborn. Robb’s honor leads him to break his alliance with the untrustworthy Walder Frey, which is his ruin. He can’t control his mother, who frees his main bargaining chip, Jaime. Robb’s death at the Red Wedding is the ultimate counterinsurgency parable.

Lesson: If you don’t hold territory and pair your military strategy with your political one, you lose.

Outside of Westeros, Anything Goes.

North of the Wall, only magic obsidian beats the White Walkers. Across the Narrow Sea, Danerys uses saboteurs and battering rams to win Mereen, a repudiation of dumb-ass Viserys’ belief that Dothraki horselords should act like Westerosi cavalry. This ain’t Westeros, so how will Westerosi commanders deal with the coming ice and fire? (Get it?)

We may learn in ”A Dance With Dragons,” which mostly takes place outside Westeros. But when in doubt, stick ‘em with the pointy end.