I dunno, I'd rather see an AC-130 H/U/J/W or an Apache in the air above me providing continuous support rather than a few strafing runs from a fast moving A-10.
The A-10 can get to the scene faster, that's about it.
Quoting my own comment from another subtree below. AC-130s circle low and slow, and cannot maneuver quickly, which makes them very very good SAM targets. The A-10 is very maneuverable and quick by comparison.
After an AC-130 was shot down in Iraq, they only fly at night.
Medium speed, but not low, they're pressurized and all of the equipment can operate at very high altitudes. The A-10 is designed to operate below 1,000 feet, low and fast. The A-10 can operate in the lower 400 mph range and the AC-130 in the lower 300s, so not too much difference.
The software and sensors have always been the major limiting factors but the US definitely sees the value of the AC-130, so there's has been a good amount of money put into it, and it's paid off.
The crash in Iraq was in 1991, 23 years ago. Since then the crew size has decreased, software has gotten exponentially better, hardware has gotten dramatically better, and they've learned from incidents to protect the crew.
Large SAM targets should always be taken out first with cruise-missiles or bombs from a high altitude. Handheld SAM launchers like the one that shot the AC-130 in Iraq down are possible to prevent with sufficient chaff (which the AC-130 has a good amount of) combined with fast enough software and senors to detect the missile. There are even more counter-measures in the new versions of the aircraft and there was a ton of money spend to preventing the loss
I really don't see why a system can't be developed these days that can effectively destroy any SAM missiles by having a dedicated cannon which can auto-target and engage any SAM, considering the processing abilities and advanced sensors available today.
The AC-130 could be the future of combat if we can perfect SAM countermeasures, which we are spending lots of money on.
Oh yeah, I forgot about flak and cannon fire from the ground. Maybe that's why it hasn't been used more. Maybe they'll be able to create advanced light-weight armor and make them autonomous eventually. Lasers and rail-guns would probably render the AC-130 ineffective though.
It's basically a flying battleship.
Here's a cool video of JATOs being used 30+ years ago:
After an AC-130 was shot down in Iraq, they only fly at night.