It will not be able to stand up to the modern fighter jets but it will be good in an ground attack roll. Some planes like that was developed, like the MFI 9 but they never got pushed into mainstream use, maybe because the military liked big, shiny toys.
It's shoulder-fired SAMs that did for piston engined aircraft over a battlefield. Back in the '60s, Cavalier Aircraft produced a modernized version of the Mustang specifically for the COIN role but its arrival coincided with the deployment of the SA-7 and an entire generation of lightweight, piston-engined combat aircraft were suddenly obsolete. These days a sensible air force uses jets (for escape velocity when chased by a missile), stays above 15,000 feet (negating the shoulder-launched SAM) and drops laser-guided bombs.