Several Republican presidential candidates, among them front-runner Rudy Giuliani, said Tuesday night they would consider using tactical nuclear weapons to prevent Iran from obtaining nuclear weapons. Asked about the possibility of using such weapons during a CNN debate, Giuliani, the former mayor of New York and one of the top contenders according to polls, responded, "I think it could be done with conventional weapons, but you can't rule out anything and you shouldn't take any option off the table." "Part of the premise of talking to Iran has to be that they have to know very clearly that it is unacceptable to the United States that they have nuclear power," he added. Giuliani slammed the Islamic Republic as "a nuclear threat, not just because they can deliver a nuclear warhead with missiles; they're a nuclear threat because they are the biggest state sponsor of terrorism and they can hand nuclear materials to terrorists." Later in the debate, Giuliani also indicated he would pick up US President George W. Bush's policy of pushing for freedom and democracy in the Middle East. "We have a country in which we have freedom of religion, freedom of press, freedom for the individual, the right to elect our own officials. And the reality is that in some of the world, much of the world, that doesn't exist," he said in response to a question on America's most pressing moral issue. "And I think the challenge for our generation is going to be, are we able to share those gifts in an appropriate way with the rest of the world? "If we can bring along the Middle East, if we can bring along those countries that are presently our enemies, and get them to see the values of these ideals... then we can end up having the peace that we want." Former Massachusetts governor Mitt Romney echoed Giuliani on an Iran strike, saying, "You don't take options off the table." "People are testing the United States of America. And we have to make sure they understand that we're not arrogant; we have resolve. And we have the strength to protect our interests and to protect people who love liberty," he said. Romney is trailing Giuliani and Arizona Senator John McCain in surveys of support for Republican presidential hopefuls, but is well ahead of the two other candidates - California Rep. Duncan Hunter and former Virginia governor Jim Gilmore - who were also asked about the preemptive use of tactical nukes against Iran. Gilmore also said no option should be ruled out, while Hunter said he would use them if there was no other way to take out the nuclear reactors. Meanwhile, at an event on faith and politics held with Democratic front-runners this week, Illinois Sen. Barack Obama was asked if Israel's treatment of the Palestinians was moral and just. "There's no doubt that Palestinians have been placed in situations that we wouldn't want our own families to be placed in," he answered, saying these situations arose in Israel's attempts at security and peace. "Israelis have been killed. They've got bombs flying into their territories right now, and we would expect them to act appropriately in defending themselves." He added that faith was connected to resolving the conflict when it came to putting aside long-standing hostilities. "It's going to require some soul-searching on the Palestinian side. They have to recognize Israel's right to exist, they have to renounce violence and terrorism as a tool to achieve their political ends. They have to abide by agreements," Obama said, adding that he expected Israel would "gladly" move toward negotiations in such a context. "But we are so far from that right now, partly because when your brothers or sisters have been killed in a suicide bombing, when you feel you're being oppressed or treated unjustly, it's very hard to get out of the immediate anger and seek reconciliation, and that's where I think faith can inform what we do," he concluded. "Faith can say: Forgive someone who has treated us unjustly. Faith can say that regardless of what's happened in the past, there's a brighter future ahead." At the same event, John Edwards, former North Carolina senator and a vice presidential candidate in 2004, was asked whether America was a Christian nation. He answered in the negative, saying that although the country has many Christian citizens, including himself, "that doesn't mean that those who come from the Jewish faith, those who come from the Muslim faith, those who don't believe in the existence of God at all, that they're not entitled to have their beliefs respected."