The question of whether the United States and Israel should sign a formal mutual defense pact is a recurring theme in relations between the two countries. It came up again in the run-up to this week's tumultuous elections as a result of public advocacy on the part of Washington and behind-the-scenes encouragement from Jerusalem.
The motivation on both sides is understandable; the US wants to demonstrate its enduring commitment to Israeli security, while the Israeli government is eager to capitalize on the pro-Israeli attitudes of the Trump administration (which have already produced significant dividends, from the relocation of the US Embassy to a formal recognition of Israeli sovereignty over the Golan Heights). But it nevertheless is a misguided effort, and one that is potentially dangerous to the long-term health of bilateral ties.
This is so for at least three reasons.
First, as former IDF intelligence chief Amos Yadlin has noted, it puts previously taboo topics squarely on the diplomatic table. If a mutual defense agreement is indeed signed between the two countries, the US will naturally need to know what, exactly, it has committed to defending. That makes the true status of Israel's nuclear program a valid subject of discussion.
It will also naturally force Israel to much more definitively articulate where it thinks its final borders vis-à-vis the Palestinians will be – since presumably US troops would be required to defend them in the event of a future Arab-Israeli or Palestinian-Israeli conflict.
Given the importance of nuclear "opacity" to Israel's deterrent posture, and the volatility of present-day relations with the Palestinians, Israeli officials shouldn't be eager to discuss either of those things in more detail than they do currently.
Second, a defense pact runs the risk of stoking anti-Israel sentiment in the US. The past several years have seen the emergence of a growing isolationist streak on the American Right, while the Democratic Party has of late tolerated mounting anti-Israel and antisemitic sentiments from its vocal progressive wing.
Both factions are likely to react negatively to any further formalization of the US-Israeli relationship. Conservatives will be inclined to view a mutual defense pact as an unwelcome commitment that forces the United States to remain in a volatile and troublesome Middle East, while liberals will undoubtedly chafe at the perception that the US has in some way become even more beholden to Israel.
At a time when the relationship between Israel and American Jewry is already under significant strain, this would be an added stressor, and perhaps a significant one.
Finally, and perhaps most fundamentally, a formal defense pact runs counter to the intrinsic nature of the "special relationship" that has evolved between the two countries over the past several decades. The strength of US-Israeli ties has historically rested on their informal nature, which has facilitated deep and productive cooperation on everything from missile defense to counterterrorism to tech innovation.
This dynamism has a simple cause: The two countries are drawn together by common values, similar political outlooks and shared strategic interests. Both Washington and Jerusalem need to continue to work diligently to reinforce this closeness, but they also need to be careful not to inadvertently take steps that alter the historic fluidity and adaptability that has helped make the relationship such a success so far.
All of that combines to ensure that, whatever the motivations, a formal mutual defense pact between the two countries will end up being a distinct liability for both. When it comes to US-Israeli ties, both Jerusalem and Washington should grasp that the current, vibrant status quo is simply good enough.