However, he loses a lot of respectability when he says that stealth is a scam. All you have to do is ask the multitude of the F117 pilots who flew over Baghdad during the invasion, if stealth technology helped them avoid Iraqi radar.
Just because SOME radars cannot detect stealth aircraft it does not immediately follow that NO radars can detect stealth aircraft.
http://aviationweek.com/defense/commentary-do-russian-radar-...
http://en.wikipedia.org/wiki/Stealth_aircraft#Limitations
http://en.wikipedia.org/wiki/Bistatic_radar
http://en.wikipedia.org/wiki/Passive_radar
http://en.wikipedia.org/wiki/Multistatic_radar
Provided that you're willing to invest a minute or so (I spent 5 min finding links) you can discover that in fact he does know what he's talking about. This is established science and not at all contentious.
Military weapon systems are a war unto themselves: each side learning about the other's and creating new systems to remove those advantages. Basically, once the F117A became common knowledge, it was only a matter of years before modern radar systems were developed that mitigated that advantage.
I have little doubt that Russia put a lot of effort into making the S400 effective against stealth aircraft. Having a low radar profile still helps, but we won't see the advantage the F117A had over Baghdad.
You can also reduce your effective cross section to long-wave radars by splitting the hull into non electrically connected areas. If there is no electrical contact there is no resonance effect for that particular frequency. Who knows, maybe some aircraft eventually will use it.
Stealth as a generic concept is not ruined by long wave radars, the current designs might be. It's traditional arms race.
Afghanistan had no serious air defence network anyway. The Iraqi air defence network was heavily outdated and under sanctions for over 10 years in 2003. The Libyan air defences hadn't been updated since the 80s when the US managed to bomb Libya with the loss of one aircraft.
The Israelis managed time and time again to overcome the Syrian air defence network. Which is, although not build to its full capacity due to Russia holding back the S300 and now heavily impacted by the civil war, more modern and better designed than anything the US encountered in her recent conflicts. And the Israelis have no stealth aircraft and used their F-15.
Question: "How did you manage to spot the stealth fighter?"
Zoltan Dani: "To that end, we used the Soviet-made P18 meter band radar which is capable of tracking any warplane irrespective of the configuration of its fuselage. The radar started to emit and we discovered a target at a distance of 15 kilometers – something that our operators were distinctly seeing on a display. I was quick to order the launch of a missile which destroyed the target."
http://en.wikipedia.org/wiki/P-18_radar
Stealth isn't a scam, but it's very much oversold, especially with regard to the F35. Ultimately the stealth of the F35 is not enough of an advantage to make up for the downsides of the aircraft. In any force on force engadgment the F35 will run out of missiles and run low on fuel before the enemies, and then it will be forced to run away. A condition where the vehicle is less stealthy and also where it's slower speed is a huge disadvantage, so it'll just get shot out of the sky. This has been the consistent result of many simulations and wargames with the F35 against contemporary fighter aircraft.