The following is a list of all GDI support powers in Global Conquest.
Once a Tier 2 base is built, GDI can organize an Orca bombing run to damage an enemy strike force. Similar to Nod's Vertigo Strike, this support power destroys at least 50% of an enemy strike force (e.g. destroys 5 Raider Buggies in a strike force of 10 Raider Buggies).
Never too selfish, GDI lends its supplies to a single city to reduce its Unrest level. This support power, as long as a Tier 2 base is somewhere on the map, is used primarily to thwart Nod's alternate victory condition (cities with full unrest that is affected by Refugee Aid will reduce Nod's progress by 1).
With a Tier 3 base, the player can call upon a strike force of GDI's elite within a GDI base's Area of Influence. Used to delay a strike force or to destroy an undefended Base with proper micromanagement, the strike force is composed of a GDI commando, 2 Sniper Teams, 4 Zone Troopers and 2 Firehawks.
A counter to Nod's stealth technology, this support power is accessible via the construction of an A-SAT Defense Center. It reveals all cloaked Nod bases and strike forces in the map, so it can be utilized to plan an attack on a Nod base. It may also be used to detect any sneaky strike forces headed to the player's base.
Part of ZOCOM's specialty, this support power is only available if a Tiberium Processing Plant is built. It covers a smaller radius than the other support power that reduces Tiberium in an area, the Emergency Cleanup, but it is able to damage Strike Forces and Bases, meaning it can be used to reduce the economy of the enemy in the next turn and harm their forces at the same time. Note that unlike Emergency Cleanup, it can only be targeted on strike forces and bases.
As one of GDI's mandates is to eradicate Tiberium, this support power further emphasizes it by reducing Tiberium level in an area, as long as a Tiberium Processing Plant is somewhere on the map. It has a larger effect than ZOCOM Infiltration, and it can be targeted anywhere with Tiberium in it.
This support power is accessible when an Intelligence Center is present on the map. Like its counterpart, the Refugee Aid support power, it lowers Unrest in cities, but it has a weaker effect and it can affect multiple cities.
Accessible via the presence of an Intelligence Center, this support power renders an enemy base/strike force unable to be ordered by its owner until the next Action Phase, as well as cancelling an order if said target already has one. This has many uses, from delaying an enemy assault to cancelling a repair/upgrade order from a base.
GDI's superweapon, it is available when its respective Strategic Structure is built: an Ion Control Center. It significantly damages enemy strike forces and bases in its target area. As what the Global Conquest Tutorial had explained, this is best used to weaken a powerful base before a nearby Strike force cleans up the mess. In contrast to C&C game logic, this support power is capable of eliminating a Tier 1 base entirely, like all Global Conquest superweapons.