In 2 Kings 18, what is the significance of the plundering of the house of the Lord?

This text is from a letter written by David Gooding in 1990.

The matter to which you call attention, namely the plundering of the house of the Lord in the cause of political and military operations, is very significant. Isaiah objected to Hezekiah showing the travellers from Babylon the treasures in his own house, let alone the treasures in the house of the Lord. Of course, it is true to say that, in cities like Babylon, the temples were centres, not only of religion but also of commerce. The temples acted like banks and they were immensely wealthy. By their investment policies in agriculture and industry, the priests exercised a very powerful influence on the economy of their own and of surrounding countries. But it is a pitiful thing to read that the kings of Judah not only took monies out of the treasuries in the house of the Lord, but also hacked the gold off the pillars and doors of the house of the Lord from time to time in order to buy off their powerful enemies.