What effects did submarines (U-Boats) in ww1

What best explains why the us government placed restrictions on asian immigration through angel island? many americans did not believe in assimilation. many americans did not approve of the gentleman’s agreement. many americans held nativist or racist views. many americans feared a loss of educational opportunities.

This was an order issued during the civil war by president lincoln ending slavery in the confederate states

The supreme court serves what important function in the u.s. federalgovernment?