The four Tech 3 Strategic Missile Launchers are the UEF Stoneager, the Cybran Liberator, the Aeon Apocalypse and the Seraphim Hastue. They are strategic units.
The Tech 3 Strategic Missile Launchers have a hefty cost of 15000 Mass. This is as much as the Cybran MonkeyLord. It actually takes relatively little time to construct, but resource consumptions will be huge. If you want to build one in a timely fashion, concentrate more on keeping a solid Mass income, than on construction capabilities.
Missile Construction Edit
Each missile (or in this case, Warheads, or Nukes) cost 12000 Mass, almost as much as the launcher itself. It takes 5 minutes for the launcher to build a missile. Although it is possible to assist the launcher, it is not recommended: With a build speed of 1080, and a Tech 3 engineer of 15, it will be mostly futile. It is best to just wait. (Assistance of 72 Tech 3 engineers or 55 Drones will cut the time to build in half.)
Always keep in mind that the missiles themselves are extremely expensive. They consume a permanent 40 Mass/s just for production, and each of them have a production cost that compares with experimental units. Because of these reasons, it is recommend to build these missiles by hand (not automatically). If your opponent has strategic missile protection, stop building missiles immediately as you are just wasting your resources.
Mind Games Edit
Although a strategic missile launcher is very expensive, it is not a bad idea to build just a launcher, without ever building missiles. This will rush your opponent into building defense, breaking his concentration, and wasting his resources on the long run. Also, it will protect your base as a deterrent (but at a lower cost): If the opponent attacks your base, you will obliterate his army before he reaches your base.
It is important to note that the opponent would need defences at all the bases that he wants to defend, necessitating the construction of multiple defences or risking a strategic missile hit. As a defence and anti-nuke costs almost as much as the laucher, multiple defences gets expensive very quickly. The upshot of this is that it greatly increases the cost of building a new base and sustaining an existing one for your opponent, requiring greater expenditure of time and effort for each base which may discourage him from building one in the first place.
Missile Damage and Use Edit
Once complete, the strategic missile launchers may construct strategic missiles, the impact of a single one of which is like the death explosion of an ACU, but much more powerful. One such explosion is sufficient to entirely annihilate most bases unprotected by strategic missile defense units. The first explosion deals a massive 70000 damage (only a few experimental units can survive it), followed by radiation, which damages units on a larger radius of 500. While this is relatively low, it guarantees destruction of smaller units and structures. The only units capable of surviving a direct nuke impact are the Galactic Colossus, Megalith, and Soul Ripper.
Strategic missiles can be used for more than just blowing up the enemy's main base and killing their ACU and, given the efficiency of strategic missile defence, they will only rarely get to do this anyway. Using nukes to take out medium-sized enemy installations and forward bases or smash large concentrations of troops before the opponent can maneuver them away can be a very effective tactic. This is especially rewarding if you can catch an experimental unit (or even more than one) in the blast; there are VERY few units in the game capable of surviving even a single nuke and few opponents expect this. Even if the nuke fails to earn back its own (exhorbitant) mass and energy cost in the units it destroys, the shock and awe effect of having such a huge hole blown in their army so quickly can give you the advantage you need to smash your opponent, and anything that does survive is softened up to the point of near-uselessness for follow-on forces to destroy with ease. However due to the missile's travel time it is usually futile to aim at a moving army unless it is being forced to move through a bottleneck; try to ambush stationary units which the opponent is assembling at a rally point. Or navy. Naval units are expensive and you will only have to get a few to make up for the cost of the warhead. Strategic missiles will kill submerged units as well. Depending on the map, you could do a lot of damage to a naval base with a single missile, two or three tech three factories, plus defences (AA and Torpedo) sonar plus whatever ships are in harbour can easilly take a chunk out of an enemy. Because they have to be in the water a defence in the main base may not have the range to protect the navy as well, requiring another defence and another missile.
A nuke attack on an enemy base can be preceded by a kamikaze air strike on the enemy's missile defence; with only 3800 hp a SMD is not too difficult to destroy and is effectively impossible to replace in time once the nuke is in the air. However, this tactic is a gamble and can be costly due to how well most players defend their SMD; it may simply be more effective to launch a slightly bigger strike directly at the enemy ACU and forget the nuke altogether. Another strategy is if you have an attack that is failing (Air or Ground) simply target everything at the SMD, so when your units are destroyed your nuke can finish the job.
Nukes will also kill ALL wreckage in the area, thus the opponent will be unable to rebuild his base quickly or reclaim that army you destroyed.
Missile Defense Edit
If the opponent has a single strategic missile defense in his base (with missiles already built), then it is absolutely useless to try to fire at it. Not only will you be wasting an expensive nuke, but you have no chance of breaking the protection: Anti-Nukes build faster than nukes, for far less resource investment and a single launcher can protect against simultaneous nuclear threats*.
(The article author can confirm a single launcher can defend against 3 simultaneous nukes, maybe more)
(Note: Ingame multiplayers test confirm that a single fully loaded launcher is able to shoot down up to 5 simultaneous nukes)
As far as factional differences go, the only notable one is the Aeon SMD. It is by far the best Strategic Missile Defense. It alone can shoot down up to 5 missiles at a time, as can be seen here, in this YouTube video.
It is also worth noting that all five missiles in the video were launched directly at the SMD. If the final defensive missile had to travel to the target, the final nuke would probably have been able to kiss the ground and your base goodbye, given in the referenced video the SMD kills it with mere nanoseconds remaining. The extra time taken for the SMD missile to reach the missile when it is not coming directly towards the SMD would cause this. This is however, unconfirmed.
One SMD can shoot down two nukes in the time it takes them to go from descending to impact in non-FA Supreme Commander. Thus you will need (number of enemy SMDs * 2) + 1 simultaneously launched missiles (this is the key part - three missiles in a chain won't break through one SMD's defensive perimeter unless it lacks missiles!) to overwhelm enemy SMDs. Aeon SMDs can sometimes get lucky and shoot down three missiles, but this is generally rather rare. It'll probably be more effective to simply overwhelm the enemy with the troops you could've bought with the resources spent on the missiles, though it is a good way of proving a point when you have the resources to spare.
The use of multiple SMD's in multiplayer is due to the fact that the enemy will have to take out multiple of these vulnerable buildings, which when spaced apart makes this no simple job. Additionally, as discussed above, it is possible a SMD may be overwhelmed, whereas multiple SMD's can fire simultaneously at multiple strategic missiles. The benefits of this are often outweighed by the cost of building the actual SMD building's themselves in the early endgame.
Veteran Status Edit
After a single successful shot at a decent target, the strategic missile launcher is usually a 5-star veteran. This is mostly useless though, except if you want to count how many units you've destroyed. This does, however, give the launcher an additional 2000 hp and cause it to self-repair at a rate of 15 hp per second for no cost, making it much harder for your opponents to destroy.
Launcher Destruction Edit
Keep in mind that when a strategic missile launcher is destroyed, is explodes for 10000 damage on a 6 radius. While it would generally be recommended not to build anything around the launcher, if you allow your opponent to destroy it, chances are he'll obliterate everything around it anyways.
Factional Differences Edit
There are absolutely no differences whatsoever in strategic missile launcher cost, damages and/or build rates. The only exception worth noting is that the Cybran missiles differ from other factions' nukes in that they are equipped with EMP warheads. Anything which survives the blast or is too close to the edge of the target area will be temporarily paralyzed by the EMP effect. This is a minor point (more insult than injury), but still one worth noting.
Another point that is worth being noted is that Seraphim warheads ( both the ordinary and the experimental one ) do NOT destroy or even damage the launcher they originate from. You can target your own strategic missile launcher and when the nuke strikes the hatch it just passed seconds ago, it won't take a scratch. However this ONLY affects this specific launcher. Any neighbouring structure, be it another launcher or not, will be destroyed. UEF, Aeon and Cybran missiles don't posses this feature.