Israeli Prime Minister Benjamin Netanyahu. (Thomas Coex/AFP/Getty Images)

Often in war, attacks on intended targets can result in collateral damage. The Washington-Jerusalem clash over the Iran nuclear agreement is a case in point. The fallout is producing casualties among both supporters and opponents of the deal that can only gladden the hearts of mullahs in Tehran.

Congressional votes on the nuclear accord are still days away, but now is the time to focus on the damage that’s being done. Left unchecked, the effects could be lasting.

Witness evidence compiled by the New York Times:

Sen. Chuck Schumer (D-N.Y.), who opposes the deal, was lampooned on the Daily Kos Web site as a traitorous rodent.

Rep. Nita M. Lowey (D-N.Y.), who also opposed the nuclear deal, said she has “been accused of being treacherous, treasonous, even disloyal to the United States.”

Rep. Jerrold Nadler (D-N.Y.), who announced his support for the deal, was called, on his Facebook page, “a kapo: a Jew who collaborated with Nazis in the World War II death camps. One writer said Nadler had ‘blood on his hands.’ Another said he had ‘facilitated Obama’s holocaust,’ ” the Times’s Jonathan Weisman and Alexander Burns reported.

And it’s not just a matter of an apparent divide among American Jews or the gulf between major Jewish organizations opposing the Iran deal and the deal’s Jewish supporters. The collateral damage falls across religious and racial lines. As a deal supporter, I know.

In response to a recent column in which I cited senior House Democrat and Congressional Black Caucus member James E. Clyburn’s (S.C.) criticism of Israeli Prime Minister Benjamin Netanyahu taking an end-run around the White House to flay the nuclear deal before a Republican-led Congress, I received this e-mail from a reader using the pseudonym “visitingthisplace”: “Black Jewish relations have always been a two way street. The Jews gave money to black causes, marched and died for civil rights, and in return, the black [sic] looted and burned the Jewish businesses to the ground. . . . In spite of your education and your opportunities, you are still just another anti-Semitic street nigger.”

But it’s more than a case of ugly words and insults.

This public battle over the Iran deal is putting a strain on relationships not just among Israel’s supporters in the United States but also between the two governments.

And the discord comes at a time when what’s needed most is consensus, as President Obama said last week, on how to “enhance Israeli security in a very troubled neighborhood.”

Admittedly, it’s hard to make an effective pitch for an end to the acrimony, since, as the late comedian Flip Wilson used to say, “Folks are so touchy these days.” But reconciliation is essential. When the dust settles, there will be a nuclear accord.

That outcome was nailed down this week when the president secured enough votes in the Senate to sustain a veto of a Republican attempt to derail the agreement.

The question that needs pondering, especially in Israel, is “What’s next?” Netanyahu evidently missed Ralph Waldo Emerson’s admonition, “When you strike at a king, you must kill him.”

The prime minister took the undiplomatic step of going over the head of a sitting president to a Republican Congress with the intention of delivering a death blow to that president’s internationally negotiated nuclear accord — and missed.

Political offense of that scale is particularly open to penalty. But Obama is bigger than that.

The “what next” question has urgency. Blocking Iran’s path to nuclear weapons for at least 10 years will not halt its aggressive intentions in the Middle East. Iran will still support proxies to destabilize opposing regimes in the region. It will continue to pose a threat to Israel. “Death to America” remains the slogan of choice at Iranian rallies.

In recognition of that grim reality, this week in Philadelphia, Secretary of State John F. Kerry outlined steps the United States will take to bolster the security of Israel and the United States’ Gulf state allies: $3 billion for Israel’s missile defense programs; enhanced funding for next-generation missile defense systems; a $1.89 billion munitions supply package; tunnel detection and mapping technologies; and giving Israel first dibs on the U.S.-made next generation F-35 fighter aircraft coming off the line next year.

Kerry said there also would be increased arms shipments and new security deals with Gulf States such as Saudi Arabia and the United Arab Emirates.

But there are breaches to be repaired.

Israel can take a step toward that end by unhitching its fate to a Republican Party blinded by anti-Obama mania. Israel needs to be a bipartisan issue in Washington.

Another positive step Israel can take? Foster a rapprochement between opposing U.S. pro-Israel camps.

The collateral damage resulting from Israel’s kerfuffle with the Obama administration may have been unintended, but it was not incidental. Never is in a war of words.

Read more from Colbert King’s archive.