The first and most obvious reason is that we are a small island surrounded by the sea. The second reason is that 30% of our land is less than 5m above mean sea level. This is equivalent to 30,000 football fields. And the third reason is that unlike other countries, we do not have abundant high grounds to retreat to.
Though the size of our reserves may be big to some, the growth of our reserves is, in fact, not keeping pace with the growth of our economy. For this reason, it would be a mistake to delude ourselves into thinking that we have more than enough firepower to defend the size of our economy in a crisis.