The U.S. Supreme Court's declaration on Friday of a right to same-sex marriage resolved a momentous question, yet the ruling left many others unanswered and is likely to spark future legal battles over gay rights.

In America, the right to marry represents only one piece in the evolving legal framework for gay civil rights.

Currently no constitutional principle or nationwide law broadly prohibits discrimination based on sexual orientation. So in the majority of states, for example, landlords can legally turn away renters because they are gay, and employers can reject job applicants over their sexual orientation.