In the fall of 2012, Israeli Prime Minister Benjamin Netanyahu appeared at the United Nations, wielding a red pen on a cartoon drawing of a bomb to warn that Iran was on the brink of building a nuclear weapon. US experts agreed that Iran's centrifuges and enriched uranium stockpiles would at that time enable Iran to accumulate sufficient fissile material for a bomb within months if it so chose.

Iran already had a delivery vehicle for a nuclear warhead then in the form of two different types of medium-range missiles that could reach Israel. During the previous 12twelve months, Iran had conducted six flight tests of such missiles. The US intelligence community was concurrently assessing that Iran could test an intercontinental ballistic missile (ICBM) with much greater range by 2015.

But it is now increasingly clear that Iran's ballistic missile systems have not significantly advanced since then — an ICBM is nowhere in sight; and with the constraints on Iran's nuclear program in the July 14 deal, the most worrisome ballistic missile threat from Iran has been defanged.

In the fall of 2013, the United States, Great Britain, France, China, Russia, and Germany (the "P5+1") had entered into intensive negotiations with the recently elected government of Iranian President Hassan Rouhani. Those negotiations soon led to an interim agreement that froze and in some cases rolled back Iran's nuclear program and ultimately culminated in the Joint Comprehensive Plan of Action (JCPOA) on July 14, 2015. This comprehensive agreement, when implemented, will severely constrain Iran's nuclear program and ensure that it is intensively monitored for many years.

Because the JCPOA will prevent Iran from arming its ballistic missiles with nuclear warheads, Iran's missile inventory looks far less formidable than it would have without the agreement. Iran's ballistic missiles armed with conventional warheads are relatively inaccurate. They can inflict pain and suffering on civilians, as happened in the "War of the Cities" during the eight-year conflict between Iraq and Iran, but they are not a game-changer militarily, nor do they constitute an existential threat to any nation.

But this is not the only reason that the timeline of Iran's ballistic missile threat is moving outward. Iran's ballistic missile program under Rouhani has focused on short-range systems. There has not been a single flight-test of a medium-range missile in three years. There has been no flight of the Simorgh space-launch vehicle, which was seen by some as a technological stalking horse for developing a longer-range military system. This inactivity has consequences for the readiness and reliability of existing systems and for research and development progress on new systems.

While eventual introduction of longer-range Iranian ballistic missiles is a valid concern, the imminence of such a development has significantly receded from what it appeared to be in 2012. Even then, before the JCPOA was concluded and a new UN Security Council resolution adopted, nongovernmental missile experts had assessed that Iran was years away from being able to deploy an operational ICBM, casting doubt on the validity of 2015 as the date for Iran to emerge as an ICBM-wielding power.

Now, the US government is finally catching up with this reality in its public characterizations of the Iranian ICBM threat. Defense Secretary Ash Carter said in congressional testimony on July 29: "I wouldn’t rule out that in 10ten years, Iran could progress to an ICBM." Slipping the potential date for an ICBM threat from Iran by a decade is a much-needed dose of reality in the often breathless discussions of the subject on Capitol Hill.

Yet even Carter's acknowledgement does not fully reveal the speciousness of the imminent threat argument some politicians are making about Iranian ICBMs.

Prime Minister Netanyahu and US Sen. Ted Cruz are among those who have asserted that Iran is building ICBMs that can threaten Los Angeles. Their political acumen may be impressive, but their understanding of rocket science and geography is not.

The minimum range of ICBMs, 5,500 kilometers, was defined during the Cold War to correspond with the rough distance between the Soviet Union and the US mainland. The comparable distance between Iran and the United States is approximately 9,000 kilometers. So "not ruling out" an Iranian ICBM does not mean "ruling in" Iran’s ability to target the United States, even within 10ten years.

Moreover, for an Iranian ICBM to reach Los Angeles, it would have to travel 12,000 kilometers. To build a weapon to deliver a nuclear payload that far would mean Iran had created one of the world's most powerful ICBMs — with a greater range than most strategic ballistic missiles in the US, Russian and Chinese arsenals.

Whatever the cause of Iran’s actual inactivity in long-range ballistic missile development, the UN Security Council has now extended for up to eight8 years a proscription on Iranian nuclear-capable ballistic missile activity and trade. That the key missile technology supplier states are thus committed will be a major impediment to any acceleration of Iran’s medium- and longer-range missile programs.

Spearheaded by persistent multilateral diplomacy and backed-up by US military and economic power, the international community is reining in Iran's putative nuclear weapons program. Faithfully implementing the Iran nuclear deal and following closely the facts on the ground will ensure that the specter of Iranian nuclear missiles continues to fade below the horizon.

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