JERUSALEM U.S. presidential candidate Mitt Romney, taking an aggressive stand on Iran, says Tehran's leaders are giving the world "no reason to trust them with nuclear material." He would "respect" an Israeli decision for military action to prevent Iran from gaining nuclear capability, a campaign adviser said. Mitt Romney: Iran Strike 'On The Table' If I Were President "Make no mistake: The ayatollahs in Tehran are testing our moral defenses. They want to know who will object, and who will look the other way," Romney says in a foreign policy speech set for Sunday afternoon. "My message to the people of Israel and the leaders of Iran is one and the same: I will not look away; and neither will my country." His campaign released excerpts of his remarks before the speech. The address by the Republican challenger to President Barack Obama was promoted as the centerpiece of a weeklong trip abroad designed to burnish his foreign policy credentials and highlight his ability to lead on the world stage. While the speech was before an audience of Israelis, the message was aimed squarely at Jewish and evangelical Christian voters in the United States as he tried to highlight policy differences with Obama.