Commentary yet to be written on President Obama's visit to Israel no doubt will be infused with readings of the congeniality meter—assessments of whether meetings between the president and the Israeli prime minister show any evidence of warming of U.S.-Israeli relations. Consensus expectations seem to be pretty low on this score, but that will not stop the meter-reading. There's nothing wrong with that on the face of it. What is wrong, however, is the prevalent assumption that warmth in this case is necessarily good, and lack of warmth necessarily bad. Warmth is good if it advances or protects U.S. interests, not if it doesn't.

In many alliances and friendships between nations this may seem almost like a distinction without a difference. There may be a reservoir of empathy, goodwill and, most important, a broad set of common or parallel interests that pays dividends to each side in ways that do not need to be connected explicitly with any one action or any one summit meeting at which leaders make nice to each other. Keeping the reservoir filled can confidently be expected to be good for the interests of one's own nation over the long term. This generally characterizes, for example, the relationship that the United States has with Britain or Canada. But the relationship between the United States and Israel is extraordinary and very different from any other—so much so in its nature and implications that it deserves to be called strange. The profuse provision of support and expressions that the larger country directs to the smaller one is not rooted in commonality of interests but instead in the larger country's internal politics.

Given the strangeness of the relationship, odd things are done about it and said about it every week, especially by American politicians. Consider an example from the chairman of the Senate Foreign Relations Committee, Robert Menendez (D-NJ), which also refers to something else this week—the ten-year anniversary of the start of the Iraq War—and extends as well to the issue of dealing with Iran, which as it is treated politically in the United States is at least as much an Israel issue as an Iran issue. Menendez begins by noting that he opposed the Iraq War, which he correctly terms a war of choice. Good for him. Then he harks back to the earlier Gulf war in 1991 and recalls that Israel's restraint in not striking back for Iraqi Scud missile attacks, because “it knew America had its back,” was an important factor in the failure of “Saddam's desperate attempt to divide the international coalition.” He's right about that, too.

But then look at the implication he draws for current policy toward Iran. He says that “our security is enhanced when the United States stands with Israel,” that “when it comes to Iran's nuclear program, it's clear there cannot be any daylight between the United States and Israel,” and “that is why” Menendez and Senator Lindsey Graham introduced a resolution that would give a green light to Israel for launching a war against Iran and pledges to back Israel to the hilt if it does so. Let's get this straight. From the fact that it was in U.S. interests for Israel to stay out of one Persian Gulf war 22 years ago, we are supposed to welcome Israel not only getting involved in another conflict but also starting it and dragging the United States into a war it would not otherwise be fighting? It is with good reason that some have called the Menendez-Graham measure the “backdoor to war” resolution. As I said, the strange relationship with Israel leads American politicians to do and say odd things.

The Israelis themselves come up with plenty of oddities. For example, they seem to have a flair for picking high-level U.S. visits as a good time to drive some more stakes into what is left of hope for a two-state solution to the Israeli-Palestinian conflict. Last weekend the new Israeli housing minister said that he wants “many, many more” Israeli settlers in the West Bank and that “there can be only one state between the Jordan River and the Mediterranean Sea—Israel.”

The Israelis are also said to be intent on pressing for release of the spy Jonathan Pollard. Never mind that Pollard, the perpetrator of one of the largest cases of wholesale selling of secrets in American history, reportedly spied not only for Israel but offered his services to other countries (including the maker of the first Islamic bomb, Pakistan) and was motivated largely by money. Note the oxymoronic comments one hears that Pollard has been punished enough for someone who “spied for an ally.” Espionage is a hostile act; it is not the act of an ally.

Let's go ahead and gauge the temperature of the president's meetings in Israel and draw whatever conclusions we want. But let's not confuse any apparent warmth we can detect with genuine friendship, commonality of interests, or an advance of U.S. interests.