Just what is apparent so far from what Israel has claimed. Control of Iranian airspace, for example, which OP of this thread claims Pakistan should help prevent. Would Israel succeeding in this be beneficial, detrimental or have no impact on Pakistan’s national interests and why?
For one, Israel already controls Iranian airspace. For two, Iran has been FAing with Israel through its proxies and now is FOing what is has sowed.
Whether that is detrimental or beneficial or neutral to Pakistan's interests entirely depends on what Pakistan chooses to do:
If Pakistan enters the fray in support of Iran, it will FO real quick too. If Pakistan chooses to help the war against Iran, it can likely derive some benefits for itself if it plays its cards right. Both options have significant downsides as well.
For Pakistan to remain neutral while making all the right polite noises and protests seems to offer the best chance of it coming out of the war next door in a neutral manner.
It is up to Pakistan to decide what it wishes to do here, of course.
McNair's paper #41 published by USAF Air University (India Thwarts Israeli Destruction of Pakistans "Islamic Bomb") also confirmed this plan. It said, “Israeli interest in destroying Pakistan's Kahuta reactor to scuttle the "Islamic bomb" was blocked by Indias refusal to grant landing and refueling rights to Israeli warplanes in 1982.” Clearly India wanted to see Kahuta gone but did not want to face retaliation at the hands of the PAF. Israel, on its part wanted this to be a joint Indo-Israeli strike to avoid being solely held responsible.
There are ten mentions of Kahuta in that report, and the relevant paragraph actually says this (
exact words follow, not what has been quoted above) on Pages 14 and 15:
India Thwarts Israeli Destruction of Pakistan's "Islamic Bomb"
There is some evidence that Iraq was not the only nuclear peril to Israel that Begin saw in the early 1980s. Nor was the Osirak reactor in Iraq his only intended target. He also feared the Pakistani nuclear effort because Israeli intelligence had found evidence that Libya and other Moslem states were helping Pakistan, supplying both money and uranium to their effort'. Pakistan's leader, Bhutto, was therefore under some obligation to share the nuclear fruits of Pakistan's bomb effort with other Moslem states such as Libya.
According to an Indian official, Subramaniam Swamy, a former Janata Party member, Israel in 1982 asked him to sound out other Indian leaders to see if India would grant Israeli warplanes landing and refueling rights were they to undertake an Osirak-type raid against the Kahuta nuclear reactor in Pakistan. India refused, probably for a combination of reasons. As one expert on South Asia speculated:
"First, the Kahuta facility is well-protected and is thus a hard target to destroy. Second and more important, India expects that any first strike by India against Kahuta would be swiftly followed by a Pakistani attack against India's nuclear facilities. Such an exchange would leave India worse off, since any potential deterrent capability against China would thereby be eliminated. Finally, India would be wary of launching such an attack against Pakistan as it would cause not only great death and destruction to Pakistan, but could blow radioactive fail-out back over India. Such an attack against Pakistan would also alienate the Muslim Middle Eastern states whose amity India has assiduously cultivated."
In 1991, India and Pakistan signed a treaty pledging that neither would preemptively attack the nuclear facilities of the other.
Please read the above for yourself. Israel's' concerns about Pakistan arose only due to links with Libya's (and others Arab states) financial support and Bhutto's foolish dreams of greater glory.
Note specifically that the claim is made by a Janata Party politician he was approached by Israel to sound out the possibilities, which were swiftly discredited due to the reasons mentioned above.
That is hardly any confirmation.
Enough said.
As long as Israel is assured that Pakistan's nuclear weapons are for its own defense against India, there is no problem. Now, please tell me again how Pakistan will gain from helping Iran now against Israel? That would seem to be ill-advised IMO, and would put Pakistan squarely in the bullseye.
FAFO again, indeed.
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Oh, BTW, the claims about what Swamy said are from the following sources:
Based on an interview granted Neil Joeck by former Janata Party member Subramaniam Swamy, January 1984. See Neil Joeck, "Pakistani Security and Nuclear Proliferation in South Asia," in Joeck, ed., Strategic Consequences of Nuclear Proliferation in South Asia (London: Frank Cass, 1986) p. 89. See also, "India Said to Eye Raid on Pakistani A-Plants," The Washington Post, December 20, 1982, p. 9; "The Islamic Bomb," in The Wall Street Journal, January 17, 1983, p. 26; and, finally, in "Four Minutes to Islamabad," Pakistan Times, April 1, 1985, p. 6.
(All media stories, nothing else.)