The other problem with the Golden Dome is that it is supposed to take out ICBMs.
Russia for example, has, according to the Bulletin of Atomic Sciences, 5,459 warheads but only 1,254 are delivered via an ICBM.
https://thebulletin.org/wp-content/uploads/2025/05/rbul_a_2494386_t0001-full.pdf
There would have to be a sub layer of intercepters placed round the coastal areas to intercept the missiles launched by subs in the coastal ocean areas.
Then the air and sea launched cruise missiles as well.
Thaad has a range of 125 miles while the Patriot system has a range of 99 miles.
Patriot targets tactical ballistic missiles and cruise missiles.
Thaad targets short, medium, and intermediate range ballistic missiles.
The length of the continental United States coastline is approximately 12,380 miles.
You would need at least 99 Thaad batteries with staffing to cover just the coastline and still leave the Northern entry open.
Patriot batteries would be in the range of 125 to cover the same area.
At 2.5 Billion USD per Patriot battery, this portion of the dome at 312.5 billion USD would eat up the estimated 175 billion USD cost for the Golden Dome with out even staffing them.