You are sooo right Indy...so why not spend the money to increase the capabilities of existing close air support al la A-10?
A-10s can't hang out on station like a flying gas can. You can't even add enough gas cans to accomplish that goal. You don't have additional crew members to effectively operate multiple sensors. An A-10 can't reload until it's landed. A 30mm in the back of a -130 can be.
Plus, they already spent money upgrading the A-10. That's what the -10C model is. It's going on right now. It still doesn't do the job they're asking of this -130.
Try looking at the whole picture...
I am, you're not. You brought up MANPADs to begin with as some great threat to it (they're not @ combat altitude), and are saying the whole idea is too expensive, and we should do something that's "cheaper" to solve it... but is actually far, far more expensive, like resurrecting & renovating out of production airframes.
The cannon they're talking about is the 30mm Bushmaster II, already in production and headed for EFVs and ships, and developed from the 25mm Bushmaster series. It's more than sufficient to plink infantry and hajii trucks from altitude.
Lets see... most popular military cargo plane on the planet, with massive additional gas tanks installed, readily available production lines, engines, and parts, proven close air support models, proven performance in extreme climates, large crew and more comfort during long duration missions, massive wing space to add more missile pylons than you can shake a stick at, more than enough room to add computer directed cannons internally.
vs...
building something completely new, or trying to resurrect out of production gear.
I need whatever you're on.