Reply #17: The problem with infantry armor is POWER.

[Xithras]

There have been numerous powered suits built for various purposes over the years, and the DoD has already experimented with arming them for combat. They are invariably passed over for one simple reason; infantry must maintain the ability to operate without supply lines for extended periods of time. Infantry armor must be fueled, necessitating solid supply lines to keep them combat ready. The two concepts don't merge well.

I've seen it mentioned, over the past few years, that the DoD is keeping an eye on some of the battery innovations being developed for hybrids and electric cars, because they may also enable them to finally make some of these weapon concepts viable. Better batteries for your Prius may one day enable Armored Infantry units to walk into combat with heavy weapons and missile launchers slung over their shoulders.