I don't believe regime change is the goal for us brother. Iranians should be allowed to govern themselves the way they seem fit, as long as they do not bring their fangs against Pakistan.
This Iranian policy seems to be out of desperation for a complete and utter failure in Afghanistan.
Therefore, we should wait until Taliban comfortably esrablishes a government in Kabul before proceeding against Iran. We need to tackle this problem together with Afghanistan, it will apply more pressure and bear more results.
It is the US which wants regime change, but remember they hyped up Hasan Rouhani as a modernist, while they lamblasted a great man and non-sectarian, Mahmoud Ahmedi Nejad, as some kind of extremist, which he was not.
Iran has very complicated politics. You have technocrats, revolutionary guard, and clerics vying for power. There are still people in Iran who are opposed to this Sunni-Shia mayhem, so as Pakistanis/Afghans, we should be supporting these people into power.
The ultimatum should be given for Iran to kick Indians from Chahbahar, or prepare for war. I think Iran will backdown. Also we should discuss with Afghans, Arabs, and Turks to apply pressure at the same time to yield better results.
Why not use Solemani's own tactic of intimidation against them?
Ironically, US goals in terms of 'Regime Change' in Iran align with Pakistan's longer term national security concerns.
Iran's influence over the world's Shia exists because of the standing of the Iranian religious leadership. The Iranian religious leadership has cleverly leveraged religious sentiment (through Shia reverence & respect for Shia religious sites and religious leadership) into support for the regime since they are one and the same. So long as the Iranian Mullah's continue to control the Iranian government, this is unlikely to change.
Khomeini did what was right for Iran, don't blame him. It was those under him who usurped the revolution, and he was powerless to control them. Then they went after everyone who was part of the revolution but did not agree with their views.
Shah Pahlavi was a brutal dictator, who was just as backstabbing as the current Iranian government, if not more so.
The Iranian regimes ulterior motives were clear In 1971 even before ceasing power in Iran when Khomeini asked his followers to use hajj gathering as political event and advertise him and his ideology.
Since then Shia Haji from Iran and other parts of the world had been going to hajj carrying lifesize posters of Khomeini and shouting political slogans.
Then the 1979 attempt of occupying holy Kaaba and annual clashes with Saudi security forces .
About safety of Shia sites. All sites have been there for over a thousand years and have been safe. Shia Iran was only created in 1979 and created this euphoria about a made-up danger to Shia holy sites which was never there. Plus creation of new "Holy sites" across Iran to make the entire country"Holy".
Plus the addition of the concept that loyalty to Iran is part of Shia faith and any Shia not loyal to Iran is not a Shia.
They achieve this by creating problems for shia in sunni majority country and then posing as saviours of Shia.
This hijacking of religion for power projection is on par with what the Vatican did to Christianity.
About Balochistan , Iranian motive in support of terrorism in Balochistan is due to large oil and gas reserves in the province. If the province becomes peaceful and Pakistan starts pumping oil and gas from there, Iran will get themselves a new regional competition in gas export.
This reason existed in Shah's Iran and support of unrest in Balochistan started soon after Sui gas exploration.
But Khomeini Iran's motives are two folds. Stop gas exploration in Balochistan and create a Shia government in every Muslim country including Pakistan .