Not absolutely related to the thread but I think it’s worth a look if you’ve not seen it before and I’m sure you’ll know what they are 
https://youtu.be/Gv9iIpeU4TE
Doing that speed at all of about 6' off the deck must have been such a rush 
Low level ground attack and general flying was the mark of some of the RAF crack squadrons. Is that still the case?
Great to witness!!

1991 Gulf War showed the vulnerability of flying low, especially using JP233 runway denial munitions, ask John Nichols. Tornado with its terrain following was optimized for this role where it could terrain follow at 50', but it was very vulnerable to small arms ground fire.
The US approach with their much bigger air force could fly above small arms ground fire at medium level & suppress SAMs and radars, through a combination of ECM and anti-radiation missiles like the AGM-88 HARM. The Gulf War vindicated the US approach.
5th generation stealth aircraft are designed to operate in modern A2D hostile environments, how well they will work in S400 defended areas remains to be seen with their range of radars frequencies & IR detection systems. Stealth technology has in the past concentrated on long range radar systems, where the current technology is at will obviously be classified.
The start of the 1991 air war was with AH64 Apaches taking out Iraqi air defence radars to create an air corridor with this article providing the best description to date I've seen
http://www.airforcemag.com/MagazineArchive/Pages/1991/October%201991/1091apache.aspx on the operation, which also illustrates the high standards to which Western forces train & operate at, which is a major asset for NATO.
About 15 years a oo I had the opportunity to fly a Chinook simulator at RAF Benson for about 10 minutes. The avionic flight control systems made it very easy as after takeoff you could set your altitude, pitch the nose forward to gain speed without losing height. Very different from flying a basic helicopter with their 3-axis cross coupling. I'm sure TB has experienced this with his models and just to takeoff and hover and land again is a major achievement.