Supporters of the Iranian nuclear deal appear to have achieved a Congressional victory. But before casting their fateful vote, they need to hear one more voice — the voice of my Israeli grandchildren. One of them is a precocious toddler named Ariel, and the other is Romi, an azure-eyed girl born last January. This is what the Iran nuclear deal means for them:

Ariel and Romi face 100,000 rockets — more than possessed by all of NATO — supplied by Iran to Hezbollah. Currently, many of these rockets can be intercepted by Iron Dome, the Israeli-designed and American-financed anti-ballistic system. But Iran wants to upgrade Hezbollah’s rockets into guided missiles capable of eluding Iron Dome and striking our military bases, electrical grids, and airport. Only the sanctions have prevented Iran from funding the upgrade. But since the nuclear deal fails to compel Iran to cease threatening to destroy Israel, the hundreds of billions of dollars in sanctions relief can help Hezbollah realize that goal. Before they are old enough to sprint, Ariel and Romi may well be rushed by their parents into shelters while missiles paralyze their state.

Israel will, of course, do its utmost to protect my grandchildren, but its ability to do so will be hindered by the Iranian deal. As the arms embargo on Iran wanes, the Islamic Republic will equip its allies — not only Hezbollah in Lebanon, but also Hamas and Islamic Jihad in Gaza — with the world’s most advanced weaponry. Shielded by its newly-purchased Chinese jet fighters and Russian anti-aircraft system, Iran can also attack Israel with hundreds of Shehab missiles, each packing a ton of TNT. To defeat the terrorists and defend its home front, Israel can mobilize tens of thousands of reservists, including Romi and Ariel’s fathers. But the nuclear deal may reduce the chances of their safe return.

The nuclear deal grants the oppressive Iranian regime, which is acting to overthrow pro-Western governments throughout the Middle East, with unquestioned legitimacy. Iranian forces are advancing to the south, east, and north of Israel, and have tried to launch attacks against Israeli civilians from the Golan Heights, a short drive from my grandchildren’s homes.

By the time they enter kindergarten, Romi and Ariel will be even more perilously surrounded. Yet the West which views Iran as a “very successful regional power” is unlikely to break that stranglehold. On the contrary, to support the Palestinians and the growing BDS movement, many of the same countries that freed Iran from sanctions may be imposing them on Israel.

Condemned to endure the very war that the nuclear deal was supposed to prevent, Ariel and Romi will grow up with little hope of peace. The deal strengthens those Palestinians most opposed to peace and deepens Israeli fears that creating a Palestinian state will merely furnish Iran with another base for launching rocket attacks. The American credibility essential to mediating and guaranteeing peace will also have vanished. Having falsely promised that Iran will never possess the right to enrich uranium and retain underground facilities, Israelis and other Middle East partners will unlikely place their trust in the United States.

And by the time Ariel enters middle school and Romi celebrates her Bat Mitzvah, Iran will almost certainly be a nuclear power. By submitting false specimens from secret sites to the UN and repeatedly exploiting the minimum 24-day delay in international inspections, Iran can cheat its way to weapons-grade uranium. Or it can wait out the ten-year period, develop centrifuges capable of enriching uranium at twenty times the current rate, and emerge the following day with enough fissile material for two hundred bombs. Weaponizing — forging a warhead and the intercontinental missile to carry it — will be no obstacle for Iran, for all of its military activity is exempted from the deal.

Yet, in addition to facing an existential threat from Iran, Ariel and Romi will also find themselves living in a highly unstable nuclear neighborhood. Arab countries in the Gulf, along with Egypt and Turkey, will not wait and see if Iran complies with what they agree is a bad deal. Rather, they will develop military nuclear capabilities of their own. In a region of incessant turmoil, the question of whether these atomic arsenals might fall into jihadist hands will always haunt these young people’s lives.

Nor can they escape that horror by traveling abroad. Iran is the world’s foremost state-sponsor of terror, plotting attacks in thirty cities across five continents. Iran is responsible for the murder of hundreds of American soldiers in Iraq, the murder and maiming of thousands of Israelis. But Iran’s support for global terror is not even mentioned by the deal. It never considers how a massive influx of cash, combined with international legitimacy, might enhance Iran’s ability to strike at “soft” targets such Ariel and Romi.

Advocates of the Iran deal must ask themselves one question. Would they support it if the lives of their children and grandchildren depended on it? Mine do. Indeed, the deal will threaten all of our families — Israeli as well as American — for generations to come.