Not all IT related hardware manufacturers are gone - this is a continual story that I hear, but I work with electronics in my job every day. We have plenty of chip and component manufacturers still in the states (TI, Intel, ATC, etc) as well as assembly houses. Many are competitive with overseas shops because of the amount of automation involved. Intel, Jabil, Teledyne, Plexus, Flextronics, Sanmina-SCI, the list goes on and on. A lot of the stuff is driven by regulation more than anything else - raw boards requiring plating processes are difficult to maintain, but even there Electrotek, Calumet, etc are still in operation and doing fine.
Our biggest issue to growth in most industries is over-regulation, taxes, and unrealistic expectations on compensation and what REAL work entails.
Lots of headquarters are here, but the physical plant is tiny and manufacturing and assembly volume are at the booutique level. When the Army or the DoD requires a half-million units of something, there's nobody on this side of the Yellow Sea that is in a position to deliver it.
I also work in the industry, and I see what goes to the warfighters. It ain't made in California.