TvT build order and strategy: Terran vs Terran

Checklist: do this

Open one factory, siege mode early, expand behind a sieged tank; identical to the siege expand against Protoss.
Vultures with mines on every path; mines are how a tank line stays safe from the side.
A starport by 5:00 for wraiths or dropships; two or three wraiths decide who can move early.
Two, then three factories; more machine shops than factories is fine, tanks are the point.
Armory by 7:00 and both vehicle upgrades; tank duels are decided by armor.
Third base behind tanks around 9:00, turrets against wraiths and drops at each base.
Drops on the main while the tank line holds; goliaths and turrets if the opponent goes air.
Late game is battlecruisers and science vessels, but only after the map is yours.

Why it works

Both players have siege tanks, and a sieged tank outranges everything on the ground, so whoever sieges first in a place wins the fight for it. The game is about positions: take the high ground and the chokes with tanks, deny the opponent's expansions with mines and drops, and never walk an unsieged army into a sieged one. Air units and drops exist to make the other player move.

If you remember one sentenceSiege first, expand behind the line, mine and drop to make them move, and never attack a sieged tank line head-on.

The build

Supply9 Time1:05 Supply Depot Never blocked early.
Supply11 Time1:35 Barracks One marine; the barracks can wall.
Supply12 Time1:55 Refinery Factory gas.
Supply16 Time2:45 Factory with Machine Shop Siege mode as soon as the shop finishes.
Supply20 Time3:40 Command Center at the natural Behind a sieged tank on the high ground.
Supply24 Time4:15 Second Factory Tanks from two factories; vultures from one.
Supply28 Time5:00 Starport Wraiths to scout and pick off tanks; dropships later.
Supply34 Time5:40 Refinery 2 and Armory Vehicle plating first in this matchup.
Supply40 Time6:30 Third Factory, Machine Shop on the second Three factories on two bases.
Supply48 Time7:30 Engineering Bay and turrets Wraiths and drops punish a base without turrets.
Supply60 Time9:00 Third Command Center Behind the forward tank line.
Supply72 Time10:30 Science Facility and fourth Factory Vessels for detection, +2 vehicle, battlecruisers later.

Research, in this order

Siege Mode at the Machine Shop
The first research of the game; the tank that sieges first wins the position.
Spider Mines at the Machine Shop
Mines guard the flanks of a tank line and kill vultures that scout.
Ion Thrusters at the Machine Shop
Fast vultures mine the whole map.
Vehicle Plating +1 at the Armory
Tank versus tank is decided by armor: plating first.
Vehicle Weapons +1 at the Armory
Then weapons, and keep both alternating.
Cloaking Field at the Control Tower
Only if you commit to wraiths; otherwise skip it.
Charon Boosters at the Machine Shop
Goliath range against wraiths and battlecruisers.

The army, stage by stage

Opening
MarineSiege Tank
One marine, the first tank sieged at the natural.
Two bases
Siege TankVultureWraith
Tanks hold, vultures mine, two or three wraiths pick and scout.
Mid game
Siege TankVultureGoliathDropship
Goliaths against air; drops on the main to force the line to move.
Late game
Siege TankGoliathScience VesselBattlecruiser
Battlecruisers only once three bases are safe behind the line.

If you scout…

A starport before a second factory

When 4:00 to 5:00

Do Turrets at each mineral line, goliaths from one factory, keep your own wraiths near the tanks.

Why Early wraiths kill SCVs and lone tanks; turrets and goliaths make them useless.

Two factories and no expansion

When 4:00 to 5:30

Do Siege two tanks at your natural ramp, mines in front, and hold; expand only when they show you the army.

Why A two-factory push beats a greedy expansion but loses to a sieged line.

A fast expansion with one tank

When 3:30

Do Match it and add the third factory early; a vulture run-by with mines into their natural.

Why Equal economies; the player with more factories wins the mid game.

Many goliaths

When 7:00 onward

Do More tanks and vultures, fewer wraiths; take the fight where the tanks are sieged.

Why Goliaths lose to tanks and are wasted without air to shoot.

Battlecruisers

When 12:00 onward

Do Goliaths with Charon boosters, science vessels with EMP, turrets at every base.

Why Battlecruisers die to massed goliaths; EMP removes their yamato.

Counters

They have	You answer with
Siege Tanks	Your own tanks, sieged first; drops behind them Equal tanks favour the sieged side; drops make them unsiege.
Vultures	Mines, tanks, a few marines early Vultures cannot fight a sieged line and die to mines.
Wraiths	Turrets, goliaths, your wraiths grouped Cloak needs detection; goliaths outtrade wraiths.
Dropships	Turrets at each base, a tank left home A drop with nothing at home ends the game.
Battlecruisers	Goliaths with range, EMP Massed goliaths melt battlecruisers; EMP stops yamato.

The mistakes that lose this matchup

Attacking into a sieged line
The sign An army gone in seconds.
The fix Never. Drop, mine, or siege in range of their edge and creep forward.
No turrets
The sign Wraiths in the mineral line, a drop in the main.
The fix Two turrets per base by 7:30 and one tank at home.
Too many wraiths
The sign Gas in the air while the tank count stalls.
The fix Two or three wraiths, then stop; tanks win the game.
Late plating
The sign Losing even tank duels.
The fix Armory at 5:30, plating first.

By level

Newcomer

Siege expand, then the cycle: SCVs, a tank and a vulture from every factory, depots ahead, another factory at 500 minerals. Siege tanks whenever you stop. Put turrets at your bases. Do not attack a sieged tank line; make them come to yours.

Learner

Timings above within thirty seconds; a starport at 5:00 for wraith scouting; the armory by 5:40; take the third base by moving the tank line, not the army; one drop on the main when the line is stable.

Competitor

Tank line leapfrog, mine placement that guards flanks, wraith micro against tanks, multi-drop play, and reading when to switch to goliaths or battlecruisers before the opponent does.