I would steer clear away from helping the Iranians.
I agree. But we can't ignore them either. As long as we are dependent on oil and gas supplies, we need to have good relations with all suppliers.
We also need Iran for an alternate access into Russia and Europe. It's required for us to compete with China in gaining access to the European market. There's a pretty good chance China will make massie BRI investments in Iran and practically buy the country.
If ever the Pakistani problem gets solved those might be the next guys we might face as adversaries.
I doubt it will come to that point. We don't have fissures between us, except maybe religion. And I doubt we will fight over religion either.
They won't buy shit from us. It's either going to be Russia,China or some European player like Sweden. The rest of the West will follow American diktat not because of some fear of the Americans but because of Iranian behaviour. India doesn't have any good system to sell to the Iranians. They are self sufficient in most things though technological inferior. We could at best sell some brahmos but the Russians will sell the oniks instead and take the profit for themselves. So it's just a waste of time...
You aren't considering what we will have when the Iranians will actually improve their economy to the point where they can buy weapons in numbers. Think post 2025.
And no, Europe will not sell Iran weapons, the Americans will make sure of that, and definitely not Sweden. Iran's only choices will be Russia and China.