1) large loss of resources, money, etc.
2) if successful, it would have eliminated the buffer zone between pakistan and the soviets, virtually guaranteeing catastrophic (to pakistan) soviet interference in an indo-pakistani conflict.
if he was actually smart, tactically, he would have left afghanistan as an unstable mess as he focused further to the south. and, if i were india, coercing him into afghanistan would actually be something i'd actively aim towards.
the web of intercontinental alliances surrounding the conflict on the subcontinent has created a sort of MAD scenario. the mutual deterrents are actually very stabilizing, in terms of deescalating clashes between official military arms. i wouldn't expect these covert "terrorist" operations to cease any time soon, but the idea that they could ever lead to large scale war is just a misunderstanding of what these tactics are; terrorism and insurgency are the conventional workaround to the impossibilities of actual war in the nuclear era. when you see these tactics increase, it signals that the nuclear option is understood to be off the table.....