“Rockets will fall on Tel Aviv,” President Obama warned on August 4, claiming that if his Iran deal is rejected, military conflict will inevitably ensue.

Mr. Obama seems to be betting that the rest of us have forgotten that Iranian rockets already fell on Tel Aviv last year.

If rockets fell when there was no agreement in 2014, why should Israelis be frightened by warnings that rockets will fall if there is no agreement in 2015?

There was a time, not so long ago, when Tel Aviv seemed immune from the dangers brewing in Gaza. Sure, border towns such as Sderot, and even Ashdod, might be menaced. But Tel Aviv is 44 miles from Gaza. Who could imagine that Hamas would have rockets capable of reaching such distances?

Then along came the summer of 2014, and with it came the shocking revelation that the latest Iranian-supplied Chinese missiles in Hamas’s arsenal could indeed reach Israel’s largest city.

On July 8, Israel’s missile defense system intercepted two rockets over Tel Aviv. Keep in mind that “intercepted” is a relative term. It doesn’t always mean that there are no consequences. When a Hamas rocket was blown up by Israel’s anti-missile batteries, it meant that shrapnel from the explosion hit whatever happened to be underneath—that could mean a highway packed with traffic, a kindergarten or someone’s back yard.

Later that day, Hamas rockets hit the Tel Aviv suburb of Holon. The next day, two rockets aimed at nearby Ben-Gurion Airport were intercepted near Tel Aviv.

By July 10, a Jewish Telegraphic Agency news report was headlined “In Tel Aviv, Sunny With a Chance of Rockets.” Correspondent Ben Sales described how as his flight from the US approached the Israeli airport, “our plane swooped in a semicircle north of Tel Aviv rather than flying directly over the city, a flight path altered to avoid potential rockets. When we entered the airport, just after the sign bidding us ‘Welcome to Israel,’ another one pointed us to a bomb shelter.”

That same day, two more rockets were fired at Tel Aviv. One was intercepted, but shrapnel from that explosion damaged cars and a gas station in the southern part of the city. The next day, 10 more rockets were fired at Tel Aviv; only six of them were intercepted.

Tel Aviv prides itself on being a city of international culture, and enthusiastically welcomes performers from abroad. But with rockets falling daily, the city was suddenly regarded as a war zone. Concerts by Neil Young, Paul Anka and the 1960s folk-rock band America all had to be canceled. The cast and crew of the television drama “Tyrant,” which had been filming in Tel Aviv, announced that they were relocating to Istanbul. (Ouch! Turkey, which supports Hamas, thus benefited from Hamas’s terror.) New York Knicks star Amar’e Stoudemire canceled the basketball camp he was going to hold for Israeli youngsters in Tel Aviv.

By July 22, rockets were hitting Tel Aviv so frequently—including direct hits on a number of homes—that the city’s famous beaches had to be shut down, at the peak of the summer season, because of all the falling shrapnel. Then came the US Federal Aviation Authority’s declaration that because of all the rockets in and near Tel Aviv, Ben-Gurion Airport was no longer deemed safe. Most major American and European airlines canceled all flights to Israel.

The rest of the story is of course well known. With Israel’s citizens under massive direct attack, and its economy about to be ravaged by the cut-off of international commerce and tourism, Israel was compelled to send its military into Gaza.

That was the reason the rockets stopped falling on Tel Aviv. It wasn’t because of anything the Obama administration did. It wasn’t because of the negotiations with Iran. It was because Israel acted on its own, in defiance of a hypocritical and indifferent international community.

So please, President Obama: don’t tell us that the Iran nuclear deal is the only way to prevent rockets from falling on Tel Aviv. We’ve seen rockets fall on Tel Aviv. We know that pieces of paper signed by terror regimes such as the one in Tehran will never prevent it.

Mr. Korn, former executive editor of the Philadelphia Jewish Exponent and the Miami Jewish Tribune, is chairman of the Philadelphia Religious Zionists.

By Benyamin Korn