Funny that USA split their efforts in missile defense between Navy, Army and Air Force, so that USA has x systems, but none of them working really good.
The only air defence systems of the US that I respect are the navy ones... on board their ships and their ships linked together with AEGIS is really the only IADS they ever really developed...
The Army stuff is a joke... Air Force cast off missiles like AMRAAM and Sidewinder and Stinger.
Patriot and THAAD have serious issues and problems and as we have seen in Saudi Arabia.... a well planned attack can completely bypass them and make them look silly.
The USN Standard system is rather more capable and is something worth a bit of respect, because together with AEGIS it is actually a proper IADS even if it is not a nationwide system protecting the US, but a shipwide system protecting groups of US ships.
As far as I know is THAAD and AEGIS not intended for the interception of ICBM. GBI is! GBI is based on the Taurus missile and a kill vehicle. It's a silo based system. Of course THAAD and AEGIS have the capabilities of ICBM interception...or let's write terminal interception of warheads.
THAAD is a theatre ABM system it was never intended to intercept IRBMs because under the INF treaty such things were banned anyway, and the ABM treaty meant anti ICBM or SLBM weapons were banned too so THAAD was designed and intended to engage short range ballistic missiles and it is not super great at doing that.
AEGIS uses Standard SM-2 and SM-6 missiles... they are two stage long missile with decent range that I would probably compare with the S-300V system if you could combine the two into one missile. They can shoot down air targets and ballistic targets and seem reasonably capable.
GBI is comparable to A-235 and it's predecessors, like Garry wrote.
Except A-235 is the latest evolution of a mature operational ABM system.
Considering that Russia now has a ring of OTH radars looking out from its borders for threats from the wave tops to deep up into space, what they are lacking is an ABM missile that is located around the place to defend more than just Moscow... which was essentially a limitation of the ABM treaty.
Now the treaty is gone and considering that unlike previous ABMs located in Moscow that had ranges of 400-500-600km at most, these new missiles reach much further and much higher, so basing them all in the ring around Moscow limits their reach... A-235 means they can be located further afield and more radars scanning the airspace inside Russian territory can be used for ABM management to shoot down a variety of targets... they could put A-235 missiles near the Northern and Pacific Fleets, near St Petersburg, in a multitude of other places where it could be useful to hit threats early.
S-500 is going to take that a step further and make roaming ABM systems a reality... whether it is on armoured trains carrying unlimited range nuclear powered cruise missiles or on ships sailing around the world able to put into port and defend the local area from any heavy ballistic attack... something unheard of previously, though with SM-6 and its relatively wide deployment on US ships something the US has had too, though S-500 seems to be going to be rather more impressive in every regard.
When they mentioned a 7km/s target speed they did say it could engage targets going faster in some situations...
S-400 can engage targets moving at 4.8km/s which means it can probably engage SLBM warheads already anyway.