Saudi Arabia has better weapons than its enemies in Yemen, no surprise in a war that pits one of the richest Arab countries against the poorest. And still the Saudis are struggling to impose their will.
Several months after his political bosses declared that the campaign in Yemen was almost over, Col. Massoud Ali al-Shwaf's border guards come under regular attack. Al-Shwaf is responsible for operations along the frontier in Najran province, where expanses of desert and mountain ravines make it challenging at the best of times to stop infiltration and smuggling. Now he's also confronted by Yemeni rebels who fire rockets from portable launchers, then bury them under rocks to escape retaliation.
"There's always engagement," the colonel said at the Beer Askar base, about 10 miles from the border, adding that his forces had repelled a cross-border attack a day earlier. "From the start of the war the threat changed and increased," al-Shwaf said. "We have the casualties to prove it."
The wider challenge for Saudi Arabia is to translate oil wealth into greater regional clout, something the country's youthful leadership has vowed to do. There were few signs of success last year. The Yemen war grinds on; in Syria, Saudi-backed fighters were driven out of their stronghold in Aleppo; Egypt, kept afloat by Saudi Arabia's dollars, has sometimes seemed reluctant to fall in line with its foreign policy.
And that policy is expensive, when the kingdom is imposing austerity at home as it seeks to rebalance an energy-dependent economy after the oil slump. The government doesn't disclose the price tag of its Yemen war, or the extent of support for opposition fighters in Syria. But the conflicts have been a growing burden at a time when plummeting oil revenues have led to a $200 billion decline in Saudi net foreign assets over the last two years. Requests for comment from the Saudi Foreign Ministry weren't immediately answered.
"The war is costing them financially, at a time that they need to focus funding on restructuring and diversification of their economy," said James Dorsey, a Saudi specialist and senior fellow in international studies at Nanyang Technological University in Singapore.
The conflict in Yemen wasn't supposed to drag on this long.
Saudi Arabia intervened in March 2015, leading a coalition that's carried out intensive airstrikes and deployed a limited number of ground troops. It's trying to reinstate a Yemeni government that enjoys international recognition yet lost control of much of the country to Shiite rebels, known as Houthis and said by the Saudis to have ties with the kingdom's chief regional rival, Shiite-ruled Iran.
Mohammed bin Salman, the deputy crown prince and architect of Saudi transformation plans, said in a March interview that the warring parties in Yemen were making "significant progress" toward resolving their conflict. Since then, peace talks have repeatedly collapsed.
"It's hard to describe this Saudi intervention as a success," said Stephen Seche, a former U.S. ambassador to Yemen who's executive vice president of the Arab Gulf States Institute in Washington. "The Saudi bombing campaign has not managed to bring the Houthis to their knees. It has inflicted enormous damage on Yemen's infrastructure and enormous suffering on the people of the country."