What were the effects of the US neutrality laws of the 1930s on American foreign policy toward the international situation in Europe?

At the beginning of WWII, the United States was officially
neutral.  This was due in part to the fact that Congress had passed laws prohibiting the
US from trading with or loaning money to countries who were at war.  As WWII went along,
these laws prevented the US from becoming directly involved and forced FDR to find
creative ways to get involved in the war.

In 1940 and 1941,
FDR found ways to help the Allies without technically violating the neutrality laws.  An
example of this was the "destroyers for bases" deal that the US made with Great
Britain.  In this deal, the US gave old destroyers to Britain (not a violation of the
laws) and in return got the rights to British bases in the Caribbean.  This did not
violate the laws, but it helped the British because it freed their forces from having to
defend those bases.  Those forces could then go fight
elsewhere.

Overall, then, the neutrality laws affected US
policy by preventing the US from direct and overt involvement in international
situations.  However, they did not prevent the US from finding creative ways to help the
Allies.