What does defaulted in Martin Luther king Famous speech?

In Martin Luther King Jr.'s famous "I Have a Dream" speech, the term "defaulted" refers to the failure of America to fulfill its promise of equality and justice for all its citizens, particularly African Americans. King likens this failure to a bad check that has been returned for insufficient funds, emphasizing that the nation has not delivered on its commitments to civil rights and social justice. He calls for urgent action to rectify these injustices and ensure that the rights of all individuals are recognized and upheld.