Prime Minister Ehud Olmert's meeting with President George Bush today comes at a critical and fluid time. Much has changed since the meeting was scheduled a few weeks ago. Yet the rise of Hamastan only accentuates the most critical topic of the day: Iran. The transformation of Gaza, almost two years after Israel's unilateral withdrawal, into a terrorist bastion openly committed to Israel's destruction, allied with the Muslim Brotherhood in Egypt, Hizbullah in Lebanon and with Iran, is a grave development. But it is just a taste of things to come if the regional power of Iran not only goes unchecked, but takes a quantum leap once Teheran becomes a nuclear power. Events in Gaza highlight the need to make a basic decision, one that has ostensibly been reached but in reality is still awaiting serious debate, let alone a conclusion. Democrats and Republicans, Europeans and Israelis, Bush and his detractors - almost all say that a nuclear Iran is unacceptable. Yet actions speak louder than words, and we can all see that international efforts to date, though having some effect, are nowhere near sufficient to force Teheran to back down. This situation, The New York Times reports, seems to have finally sparked a debate within the Bush administration over Iran policy. At a meeting to discuss where the Western sanctions campaign was going, a key architect, Undersecretary of State Nicholas Burns, let the cat out of the bag: "Negotiations with Teheran could still be going on when Mr. Bush leaves office in January 2009," according to the Times's characterization. The same report notes that IAEA predicts that Iran could have 8,000 centrifuges enriching uranium by the end of the year. This is enough to produce about five nuclear weapons a year. Accordingly, Burns's admission is a delicate way of saying that Iran will get the bomb. The US, it seems, has not abandoned an incremental approach that has little to no chance of success. Rather than asking what sanctions could be sufficient to stop Iran and pursuing them, the policy seems to be seeking the most that will fly, regardless of whether it has a chance of working or not. Olmert's job in Washington should be to help concentrate American minds. The first way to do this is to reiterate that Israel cannot live with a nuclear Iran, and will do what it takes to prevent that from happening, despite the substantial risks inherent in such a military action. Olmert must make it clear to Bush that there is no option of living with a nuclear Iran, there are only better and worse options to prevent that eventuality. As presidential candidate John McCain put it, "There's only one thing worse than the United States exercising the military option; that is a nuclear-armed Iran." That said, it is not too late to avoid the military option. If Europe imposed the trade, investment and diplomatic sanctions that the US has already imposed, along with global UN-backed financial and diplomatic sanctions, it is likely that Iran could be forced to change course without firing a shot. The question, then, is not whether Iran can be stopped, but whether it will, and by which means. The refusal to take serious non-military measures is leaving a choice between the much more dangerous and unpalatable options of taking military action now, or standing by as the jihadists - from Gaza to Lebanon, to Iraq - gain a nuclear umbrella. There is much that Bush and Olmert can say and do to address the symptoms of the rising jihadi axis, such as Hizbullah's rearming in Lebanon, Hamas's rearming via Egypt and the terrorist challenge to Iraq's nascent democracy. In the end, however, these are all battles with Iranian proxy forces, and cannot be fully addressed except at the source. Indeed, to the extent Washington and Jerusalem allow Teheran's proxies to distract from the real challenge, they are playing into the mullahs' hands. Accordingly, whatever messages emerge from the White House today, however many of them are welcome and important, there is only one that really counts: a clear commitment to prevent a nuclear Iran, backed by a policy with the teeth to fulfill it.