Defence expenditure is the premium paid to insure against the failure of foreign policy
A good defence strategy is one that manages the risks of foreign policy going wrong for one reason or the other. It might turn out that foreign policy was based on the wrong presumptions, or unexpected events might upset the geopolitical balance and so on. In these circumstances, a state should have the military capacity to ensure that its interests are protected. In other words, work for the best, but prepare for scenarios where the best doesn’t happen.
It follows that there is a good reason to keep the foreign & defence policy establishments at a sufficient distance in order to prevent confusion on their respective objectives. They must co-operate and co-ordinate at some levels, but it must be recognised that defence expenditure is essentially premium paid to insure against the failure of foreign policy.
There are two mistakes states can make: subordinating defence strategy to foreign policy and vice versa.
Nehru’s policy of non-alignment (as distinct from participation in the Non Aligned Movement) in the years following independence was infused with realism. But he failed to (and indeed refused to) invest in building the necessary military capacity to hedge against the chance that non-alignment might fail. In the event, he had to seek urgent military assistance from the United States in 1962 after the Chinese invasion.
Pakistan is an example of the other mistake. Its foreign policy is completely subordinate to its military strategy. It is eminently sensible for Pakistan to develop military capacity to defend itself against India. But it is high folly to then pursue a foreign policy of relentless hostility and antagonism towards its eastern neighbour.
The takeaway from this little post is that an essential question that foreign policy analysts must ask is—are the goods sufficiently insured?