How much US tax $ is being spend by the military to protect Exxon & Brit oil corporations in the middle east?

We're spending quite a bit to protect our oil shipments. To be fair, it's not just us in the Gulf doing this. I have seen naval units from France, Britain, Australia, and the Netherlands there too, but it seems that we spend much more than they do, and perhaps it's time that all the countries who export oil from that region spent a bit more in support of our efforts to protect their oil shipments.