I agree with Coota,
Building on what you say with regards UK/US military ties and the role BAE Systems now plays in the US. Through ownership of United Defense, a UK company effectively produces/maintains a large slice of current US Army ground systems as well as participation in JSF, T-45 Goshawk and the AV-8 Harrier programmes.
With regards the US Army alone, such equipment includes:
- M2/M3 Bradley Family of Vehicles
- M88 tank recovery vehicle and the M88A2 Heavy Equipment Recovery Combat Utility
- Lift and Evacuation System (HERCULES)
- M109 155mm self propelled howitzer, including current M109A6 Paladin
- Amphibious Assault Vehicle
- M9 Armored Combat Earthmover (ACE)
- M113 Family of Vehicles to include armored personnel carriers, medical, command and control, engineering and mortar carrier vehicles.
- M777 155mm Lightweight Towed Howitzer.
- US Army Future Combat System, (Non-Line-of-Sight Cannon and the Armed Robotic Vehicle).
I doubt other non-US defence producers like EADS or Thyssen-Krupp would ever be given such opportunities in the US domestic defense market.