Qatar is a big fish in the world of liquefied natural gas but a relative minnow when it comes to oil. The Middle Eastern nation, which was targeted by a Saudi Arabia-led alliance over Iran tensions Monday, is the world’s biggest producer of the super-chilled fuel, shipping out more than 30 percent of global exports last year. By contrast, the OPEC member accounts for only about 2 percent of the world’s oil supply. Qatar’s geography is more important to the oil market, as it sits near the three largest OPEC producers — Saudi Arabia, Iraq and Iran — and the crucial chokepoint at the Strait of Hormuz.