Eli Lake has a blockbuster story today on discussions between Israel and the U.S. on agreed upon triggers or “red lines” that would determine when to launch a military response against Iran. Lake reports:

When Defense Secretary Leon Panetta opined earlier this month that an Israeli attack on Iran’s nuclear facilities could “consume the Middle East in a confrontation and a conflict that we would regret,” the Israelis went ballistic behind the scenes. Michael Oren, Israel’s ambassador to Washington, lodged a formal diplomatic protest known as a demarche. And the White House was thrust into action, reassuring the Israelis that the administration had its own “red lines” that would trigger military action against Iran, and that there is no need for Jerusalem to act unilaterally. . . .

The stakes are immensely high, and the distrust that Israelis feel toward the president remains a complicating factor. Those sentiments were laid bare in a speech [Benjamin] Netanyahu’s minister of strategic affairs, Moshe Ya’alon, gave on Christmas Eve in Jerusalem, in which he used Panetta’s remarks to cast doubt on the U.S.’s willingness to launch its own military strike.

It should come as no surprise that there are differences between the two governments over what the intelligence data mean. The argument is more than academic: “The intelligence disagreement is significant in part because one of the factors in drawing up red lines on Iran’s program is how much progress Iran has made in constructing secret enrichment facilities outside of Natanz, where IAEA inspectors still monitor the centrifuge cascades,” Lake writes.

So what to make of all this? First, it’s remarkable that Panetta should make such a mess of things just at the time delicate discussions were going on. Mark Dubowitz of the Foundation for Defense of Democracies and who was instrumental in helping to craft sanctions legislation, e-mails me: “Panetta didn’t go off the reservation. He expressed a view that is widely held in the administration and that his predecessor Bob Gates also publicly expressed. But it is a view that is rapidly being overtaken by events as centrifuges keep spinning, sanctions weaken Iran but don’t change the regime’s nuclear calculus, and Israelis fear that a nuclear armed Iran may only be truly unacceptable to them.”

Another analyst critical of the Obama administration agrees with Dubowitz. Willing to talk only on background, he explains, “Panetta got that far off the reservation because the administration is divided about what to do, the president sends uncertain signals to the rest of his government and, most directly in the case of Panetta, the senior military is decidedly trying to avoid any military conflict with Iran. Many in the military don’t believe it is necessary, some believe a decisive blow against the program is now impossible in any case, and perhaps most believe the military simply cannot afford another war given budgets and force readiness levels.”

But it’s clear that agreeing upon “red lines” simply moves the debate to an ostensibly technical argument as to whether Iran has crossed them. But in reality, the discussion concerns the acceptable level of risk each country is willing to undertake. Dubowitz says, “The debate will be over whether or not the intelligence demonstrates conclusively that these red lines have been crossed. Expect a debate between Israeli and American intelligence communities on these questions.”

A critical open question remaining is whether it is too late to enact sanctions and wait for results. Dubowitz contends 2012 will be the decisive year. He says, “This needs to be the year of a rapidly cascading set of oil sanctions designed to hit the regime’s wealth and threaten its survival.”

Others are more glum, believing that sanctions will be delayed or watered down and arguing that it’s impossible to know with certainty what the Iranians are up to. One defense expert says, “What people forget is that military preemption is often necessary precisely because one can’t predict with precision what the future holds.”

Ironic, isn’t it, that Obama should find himself in the same predicament as his predecessor: Preemptively strike a rogue regime or run the risk of regional and global catastrophe? There is one big difference, however. In Obama’s case, the Israelis will act if we don’t. And the margin for error, the degree of risk Israel is willing to incur, is much smaller than for us. Its existence and the entire Zioinist concept of a safe refuge for Jews is at stake.