Rouhani , Matthew Wallin : U.S. president Rouhani shows signs of wanting to resolve nuke issue . They say Congress Sunday will offer chance to affirm this . `` Negotiations with the Iranians is always difficult , '' Obama said to George Stephanopoulos on Sunday . Do his words matter ? They say Iran , U.S. both testing . Iran will want concrete actions before easing sanctions . Writers : Congress must be flexible and be willing on diplomatic solution .
Rouhani , Matthew Wallin : U.S. president Rouhani shows signs of wanting to resolve nuke issue . They say Congress Sunday will offer chance to affirm this . Do his words matter ? They say Iran , U.S. both testing . Iran will want concrete actions before easing sanctions . Writers : Congress must be flexible and be willing on diplomatic solution .