Its not banking on the US but mere common sense. The US will not tolerate any activity that enriches Iran, it has successfully forced the Indians to back out of the IPI deal and forced the Indians to reduce their appetite for Iranian oil.
You do realize that US tried but failed to get India and China to cut their consumption of Iranian oil?
This despite Saudi Arabia offering to cover the entire amount of oil that they would reduce from Iran?
And that it is a breeze paying KSA instead of Iran?
Why then are both India and China buying oil from Iran?
And why is it that both these countries have been
exempted from US sanctions?
Not really. American strategic planners have realized that it is in the interests of the US to ensure that both Afghanistan and Pakistan are stable. This is why the Americans have shoved down billions of dollars in both Afghanistan and Pakistan to try and stabilize the situation. They have realized that their strategy in Afghanistan was flawed by not including the Pushtuns, this is why the Americans are now openly embracing the Taliban and opening up peace talks with them. If they wanted Afghanistan to remain volatile, they would have never made overtures to the Taliban. It is in the political interests of the US that both Afghanistan and Pakistan remain stable and prosper, State Department was quite explicit in that.
The State department may be explicit, but US actions and words dont always match.
So you admit, the US was successful in its goal. It has everything to do with influence, whether you like it or not but the US remains to be the sole superpower when it comes to diplomatic, political, economic and military clout. Through their chokehold on the Global Financial System, they were successful in reducing China's and India's oil appetite for Iranian oil.
They were successful in reducing it, but as I mentioned above, they were not successful in eliminating it. And that is only India and China who are exempted from the oil sanctions on Iran, despite KSA offering to take up any slack.
Indeed, they offered something to the Indians they simply could not refuse. In case of Chahbar, they don't have to offer anything because the Americans are the top dogs in Afghanistan and India is at best a 'Non Entity'. India lacks the political, diplomatic and military clout required to be a major player in Afghanistan. Its a sad reality but unfortunately it is the reality.
You dont get it.
Americans are the top dogs in Afghanistan and India might be a non entity or a super entity. That is irrelevant. What India wants is a way to ship goods to and from the Central Asian Region along with Afghanistan.
Iran offers that by way of Chabahar - a port developed with Indian assistance.
US would again have to make an offer that India cannot refuse to let this port go and not use it.
Whether they would or not remains to be seen. But at the moment, things seem to be headed in the direction of an operational port in Iran and trade with India.