It takes time and effort to build an international coalition to establish a no-fly zone over Iran. Despite the P5+1 still entertaining desperate hopes about reaching an agreement with Tehran, there is absolutely no chance that such an agreement will be clinched for the simple reason that such an agreement is not in the interest of the Khomeinist regime as any agreement would be abrogated by the next Republican president in the US.
As the collapse of the JCPOA is already a fact, the question is whether the US will join the emerging coalition to impose a no-fly zone over Iran with air support to armed rebellions once the JCPOA is officially declared dead? This is all but certain as the US has very few options at its disposal and the US not joining the coalition would very significantly increase the risk of the US having to resort to invasion if the insurrection fails in Persian areas. This is because Iran plans multiple waves of mass terrorist attacks with chemical weapons against major American cities in order to force the US government into submission and ensure that President Biden behaves like a proper Dhimmi (non-Muslim Islamic subject). America has three wannabe superpower rivals and not two as is typically presumed.
If America is fully part of the international coalition would it make sense for America to also implement the destruction of the Iranian nuclear weapons program and not wait for Israel to complete its project which will be ready for military implementation at the earliest in the fall of 2022. It would seem quite unreasonable to unnecessarily delay the operation only to await the completion of Israel’s capabilities as America’s capabilities are ready for use at any time.
However, there is also the issue of America being forced to invade if the insurrection fails in Persian areas of Iran (it is guaranteed to succeed in the ethnic periphery where half the population lives) and hence necessitate an American invasion of Persia to prevent further waves of Iranian chemical weapons attacks against major American cities. Building up such a massive ground force in the region will take quite some time but will be rather necessary in consideration of American national security. However, the buildup of massive American ground forces in the region prior to attacking Iran from the air will quite possibly deter Iran from attacking major American cities with chemical weapons. Iran knows that America has no appetite for an invasion but if there is already a massive American force buildup ready to invade if the given the order could that very well deter Iran from attacking America with weapons of mass destruction.
The Democratic administration made a severe miscalculation and wasted one year trying to appease totalitarian Iran. In the process the administration has completely lost its credibility and US deterrence vis-a-vis Iran is completely destroyed. The only way to restore US deterrence and to protect the American homeland from Iranian attacks with weapons of mass destruction is to amass major US ground forces ready for an invasion if given the green light. This massive military buildup will need to take place in the months prior to the imposition of the no-fly zone and the destruction of the Iranian nuclear weapons program. The purpose would not be an invasion but to protect the American homeland and prevent an American invasion becoming necessary and to achieve this by means of conventional deterrence.