If you play with Terran against a Terran you can make this tactic to defeat your enemy.But firstly you must cover the enemy by turrets and especially some strategical points you must consruct some bunkers to control the enemy expansion, then locate some Tanks which will prevent enemy movement to the critical points.While you are constructing your large(global) defense you must develop Goliath and Drop Ship technology.After these movements you must select the best location to drop; this location can be the fresh mineral site of your enemy or macro construction center.This tactic can be supplied by some Battlecruisers but here you must control lots of expansions to obtain enough mineral.Economy will always be an advantage so do not deny the SCV capacity!