The army has the overall advantage in T2 (whereas the Cybrans are superior in T1 and Aeon in T3) with the gatling bots, but is weak in T1 with terrible Mobile AA and average units overall. The UEF air has an enormous advantage with the Fighter/Bomber, fast to build, great bombs with a large area of affect, and adequate AA. If you can surprise an enemy with no air cover or shields, ten fighter/bombers can kill their ACU in two minutes or less. The Governor Class is a flawless warship for T2 standards. Long range with missiles, T3 AA, and cannons; the UEF cruiser can single-handedly destroy an enemy base; that is, unless it has multiple artillery or a battleship hanging around.
The UEF units are often favourites since they do decent damage per shot (do not get this mixed up with DPS; it means that each 'bullet' does significant independent damage), are more heavily armoured than their opposing factions' counterparts, and are not any more expensive. The cost for their high armour values and powerful weapons is agility; their land units' speed is very heavily compromised, meaning that a knowing commander will often attempt to use transports (a fact assured with the T3 Continental Transport); their sea vessels turn, move, and react slower than their counterparts; and any turrets, on defensive installations or units, move much more sluggishly than their equals from the other factions. This brings up the problem of a flanking attack, since a sizeable force may be able to destroy unsuspecting turrets looking the other way before they can react and return fire.
The UEF T3 bot Percival is a formidable unit with higher DPS and health than the Cybran brick. Even in small numbers, they can assist in assaulting bases while soaking up damage. However their slow firing rate makes them better suited at attacking buildings and wearing down shields while T2 units do the bulk of the short range fighting.
The T3 Summit-class Battleship, with its three triple gauss cannons that do massive damage per shot, is a master of support bombardment from the sea. Its equally-massive health bar (51,000 health points!) gives it a distinct edge against other battleships in being able to fire against specific targets while being very hard to sink, especially when supported. One of these can turn the tide of a land battle, two or three are able to deal heavy damage to enemy experimentals, while four or more can almost conduct the battle themselves.
One other advantage the UEF has is the Fatboy, a god in the experimental community. Amphibious, long range battleship/triad guns, shields, and AA; the Fatboy can destroy opposing armies or experimentals before they are in range to return fire, but unlike most other factions' main land experimental, it has to be used intelligently. It should not be thrown straight at an enemy experimental or frontline, but should in fact bombard it from a distance, perhaps even moving away while firing to give the maximum amount of fire time possible.
UEF bases in the campaigns are constructed very block-wise and squared off; often times you will find a very symmetrically constructed base by the UEF. Whilst this has good advantages, space-wise, as all buildings in the game are constructed as squares or rectangles, this often makes problems arise such as defending efficiently or shielding well, since the average player makes their bases as tight-packed as possible and shield facilities are often built near the outside. Since they are only constructible at T2 and up, and defence mechanisms must be built outside of the base to defend, this brings up problems such as if the enemy brings gunships into the base out of external anti-air turret range. Another problem with the UEF is the apparent 'sluggishness' of their units in general; they turn and move much slower than their Aeon, Cybran, and Seraphim counterparts, which is a hazard when trying to defend a flanking attack. Perhaps the most obvious difference in their ability to defend well when compared to other factions is their ability to build a T3 Point Defence - The Ravager. With a higher DPS and a longer range than any T2 Point Defence, they are deadly against almost any enemy, experimental or otherwise. Like most of the rest of their units and buildings however, it too is "sluggish", but mainly in its reload times. It will fire continuously for a short while, and then has a long reload time, making it not ideal when used against any T2 or lower units. Ravagers therefore should not replace T2 Point Defense entirely, but rather supplement it. Considering these issues, a critical skill for a UEF commander is to plan your base layout in advance. Adequate space should be left for Ravagers and shields in advance, even if it leaves a small hole in your base for a while - consider filling these spaces with Mobile Shield units until your stationary versions can come online.
An advisable strategy when playing as the UEF is to upgrade techs as quickly as possible and build shield generators near the center of the base; this will keep them from unnecessary damage, will protect more efficiently due to the UEF's longer shield range, and will guarantee the shield generator a better survival rate when upgrading. Also, if you are turtling, build a decent amount of turrets in a sparse 'turret ring' around your BOA. This will help damper the slow turning rate of the UEF turrets since different turrets defend different areas. The UEF is not advised for 'rushing' the enemy at early stages of the game as their land units are slow and all except one T2 unit do not hover like Aeon and Seraphim T1 units do. The Aeon and Seraphim will be the most dangerous units around in the beginning since their T1 units can hover over natural water barriers, are very quick, and deal serious damage at the early periods of the game with their higher-powered and accurate lasers. As the UEF, defending your line is the key to survival and success, as their units seem to have been made for defending and surviving rather than swarming.
The UEF ACU is another destructive element of the faction, but almost always goes unnoticed. It is the most heavily armored of all the ACUs, but their weak direct-fire capabilities and low muzzle velocity renders it obsolete around direct T3 land battles. But what makes the UEF ACU truly shine is its ability to become a tactical missile launcher. When upgraded, it can act as a mobile TML, with the long range remaining, unlike the standard T2-T3 mobile TMLs. That, added with its ability to remain underwater, makes it a near-invincible, long range attacker, unless of course the enemy uses torpedoes, but that can be dealt with before having the ACU sent underwater. Having SCUs assist the ACU in building its TMs will give you a near-endless rain of missiles that can rival that of the Spearhead, and even the Aeon Torrent class in ROF, which can be used to overwhelm and destroy TMDs and other defenses, for an unimpeded assault. This ability enables a UEF player to strike at defenses at a safe distance, therefore lessening the effort and resources needed to break through a base. But the most destructive feature of their ACU is their ability to turn these TMs into nukes. Called "The Billy," it is basically a tactical missile that has a nuclear payload. It's blast radius and damage is half that of a real strategic missile, but only sturdy units like Experimentals and T3 factories can withstand it. Because it is still technically a tactical missile, it can be intercepted by TMDs, but also because of this, it doesn't trigger a Strategic Launch warning and cannot be intercepted by SMDs, making it very unpredictable and confusing. An ACU with 5 SCUs assisting, which can fit in one Continental, underwater, with ASFs, torpedo bombers, and naval units on standby to assist when needed, can annihilate a base.
Against the UEF, the best attack strategies revolve around flanking. Take advantage of the UEF's apparent 'sluggishness' and let T3 and T4 units soak up the main fire as faster units creep behind and destroy the unsuspecting and slow rear defence turrets and structures. The more quick or heavily-armoured units you can use in an attack, the better, since the projectiles they use do serious damage in often area-of-effect. Last of all, attempt to use very quick and high-damage units to kite around the edges of their unit's firing range and attack them whilst the turret attempts to keep up (the Blaze Aeon assault vehicle is a natural choice since it will usually automatically strafe while attacking because of its hover capabilities, although the lack of a moveable turret will pose problems when attempting to kite). A group of Flare T1 bots can run around a UEF Triad almost indefinitely since the Triad's projectiles are horrible at tracking moving units, but the Flare would most likely only do minor damage before its destruction.
The UEF is heavily armoured, but can lack the unconventional 'surprise' weapons of their competing factions. UEF bases and armies are based around emerging modern warfare technology, and their experimentals are a perfect example of this. The Fatboy is a classic futuristic mobile battlestation, the Atlantis is a modern flagship carrier with the advantage of submersibility, the Novax Center is a control centre not unlike modern-day examples, and the Mavor is a standoff finishing weapon to soften or completely destroy the enemy's base(depending on the circumstances). As such, units such as the Salem Class with their walking abilities can easily take a 'sluggish' UEF turtle player off-guard. They have a very average unit lineup in the early stages, so you will have to rely on classic army strategies until you get to T2, rather than Seraphim T1 artillery spamming or stealthy Cybran scouting.