Indian Armed Forces into Pakistan on a large scale may elicit a nuclearized massive retaliation, if and only if the Pakistan Army is unable to stop such intervention. For instance, many analysts, including some Indians, believe that the Indus Valley— the "lifeline" of Pakistan— is one of many other "red lines" that Indian forces should not cross. The capture of key objectives in this crucial northeast–southwest axis might well provoke nuclear retaliation by Pakistan. Military threshold - The complete knockout or comprehensive destruction of a large part of the Pakistan Armed Forces, particularly and most importantly the Pakistan Air Force (PAF), could lead to a quick nuclear response if Islamabad believed that it was losing the cohesiveness of its defence and feared imminent defeat. A senior ranking PAF officer maintained that "orders given to PAF (and its missile command) are identical to the guidelines given to the NATO commanders during the Cold war crises". This criterion is even more important for the Pakistan Armed Forces because of its critical role in maintaining the country's stability. As noted above, an attack on a nuclear installation has also been posited as a threshold. According to the PAF, this threshold would also be breached by the use of chemical or biological weapons against Pakistan, and would provoke a massive retaliation. Economic threshold - This level implicitly and explicitly refers for the countermeasure operations of the Pakistan Navy. Economic strangulation and economic blockade is also a potential threat to Pakistan, if the Navy is unable to counter it effectively (for example, see operations: Trident and Python in 1971). This primarily refers to a potential Indian Navy blockade of Sindh Province and coastal cities of Balochistan Province, or the stoppage or significant reduction of Pakistan's share of water from the Indus, Jhelum and Chenab Rivers under the 1960 Indus Waters Treaty. It could also refer to the capture of vital arteries such as the Indus. Political threshold - Finally, Pakistan's geostrategists, game theorists, political strategists and planners suggest that a destabilization of the country by India could also be a nuclear threshold if Islamabad has credible reasons to believe that the integrity of the country were at stake. Stated scenarios are political destabilization or large-scale internal destabilization which the Pakistan Marines (along with the Civil Armed Forces) are unable to stabilize effectively. One example would be encouraging the breakaway of one or more of Pakistan's