1.India has designed it's own Arjun Series tanks. It's shortcoming that is that it is a heavy tank ( 70 Tonne) , thus most of bridge in Punjab could not support it,and it is costliest Tank in world ( $11 million per piece).It was developed at a time when Pakistan was rumored to be purchasing M1A1/2 and India has to field a heavy tank in order to counter it.
2.India has varied geography. The type of tank that would be operable in Israel would also be operable in Indian Desert which make up 60% of Indo-Pak border. Though it would be useless for Himalayan operations where a light tank is required and in Punjab where a Tank would need to be able to cross network of canals.
3.The next project FMBT Karna is also expected to be a heavy tank ( though of lesser weight than Arjun ). India could not team up with China (obviously), Russia ( Russia is into light tanks), Germany ( not interested even in upgrading Leopard, forgot new series of tanks ), USA ( USA never goes for tech co-operation), Japan ( no military cooperation clause in their constitution, else Japan would be first choice) . SO natural partner, if a partner is required , would be Israel. A partnership would compress timelines of development and India would need not develop all tech inhouse, especially active countermeasures like Trophy and Iron fist.
Current Barak-8 QR-SAM development is a good template for joint development. Workload of that missile has been shared between DRDO and IAI.Israel benefits from such projects as they provide economy of scale which Israeli military could not provide, alone ( ex: Indian Navy has 2 Aircraft carriers,9 landing ships,19 destroyers,16 frigates, and 25 corvetts while Israel only has 3 corvetts).
4. Israel is ready to supply us with tech which US is not wiling to supply US. France and Israel are major source of western tech for India.
....
...
