Why did Australia refuse to send a single ship to the Red Sea?

Plus, somewhat incredibly to those of us who've been watching the Ukraine war now for the last two years, none of our ships can defend against drones, outside of their ultra-expensive missiles.

This points to another factor-the relentless degradation of our military forces by both sides of politics.

Somewhere around 2 percent of GDP is generally accepted as a reasonable figure to spend on defence. It's the standard expenditure NATO members promise.

We've rarely met that figure outside of wartime. In 2007, at the end of the Howard Liberal government, we spent 1.56 percent of GDP on defence.

There was a slight decline over the Rudd-Gillard-Rudd Labor governments to 1.51 percent, and then an increase to around 1.98 percent of GDP under the Abbott-Turnbull-Morrison Coalition governments, which it appears Labor is going to maintain.

So Australia has decades of underspending-probably not wise when the world average is 2.2 percent and we live in such an isolated part of the world.

The United States spends 3.5 percent of GDP, Russia 4.1 percent, Israel 4.5 percent, South Korea 2.7 percent, and India 2.4 percent.

The size of population, and size of territory also matter.

Singapore, which is a tiny island, spends 2.8 percent of GDP, while China, with a huge landmass, but also a huge population spends only 1.6 percent.

In absolute numbers, Singapore is spending US$11.7 billion, while Beijing spends US$292 billion. The United States spends US$877 billion.

Efficiency of spending also counts. Manufacturing in the United States is a lot more expensive than manufacturing in China, so it's quite possible China is getting a much better bang for its buck than the United States and is therefore in a more competitive position than the figures might suggest.

And then there is the size of the defence effort you are trying to maintain.