Canonical, SHEILD is independent from any nation because defending the world can't be the work of any one nation.
Problem is, Disney has a deal where if they write jingo trash the US military gives them toys to play with. That's why the international SHEILD is portrayed as using US military hardware.
SHIELD is basically super-powered NATO. At first glance it looks like a voluntary multi-national coalition set up to defend against outside threats, but it's really just the US in 30 different trench-coats, doing whatever is necessary to protect the Empire.
Canonical, SHEILD is independent from any nation because defending the world can't be the work of any one nation.
Problem is, Disney has a deal where if they write jingo trash the US military gives them toys to play with. That's why the international SHEILD is portrayed as using US military hardware.
SHIELD is basically super-powered NATO. At first glance it looks like a voluntary multi-national coalition set up to defend against outside threats, but it's really just the US in 30 different trench-coats, doing whatever is necessary to protect the Empire.