According to the BBC article, “Yemen crisis: Who is fighting whom?“:
“Yemen, one of the Arab world’s poorest countries, has been devastated by a war between forces loyal to the internationally-recognised government of President Abdrabbuh Mansour Hadi and those allied to the Houthi rebel movement. More than 6,800 people have been killed and 35,000 injured since March 2015, the majority in air strikes by a Saudi-led multinational coalition that backs the president. The conflict and a blockade imposed by the coalition have also triggered a humanitarian disaster, leaving 80% of the population in need of aid.
The conflict has its roots in the failure of the political transition that was supposed to bring stability to Yemen following an uprising that forced its longtime authoritarian president, Ali Abdullah Saleh, to hand over power to Mr Hadi, his deputy, in November 2011. Mr Hadi struggled to deal with a variety of problems, including attacks by al-Qaeda, a separatist movement in the south, the continuing loyalty of many military officers to Mr Saleh, as well as corruption, unemployment and food insecurity.
The Houthi movement, which champions Yemen’s Zaidi Shia Muslim minority and fought a series of rebellions against Mr Saleh during the previous decade, took advantage of the new president’s weakness by taking control of their northern heartland of Saada province and neighbouring areas. Disillusioned with the transition, many ordinary Yemenis – including Sunnis – supported the Houthis and in September 2014 they entered the capital, Sanaa, setting up street camps and roadblocks.
In January 2015, the Houthis reinforced their takeover of Sanaa, surrounding the presidential palace and other key points and effectively placing Mr Hadi and his cabinet ministers under house arrest. The president escaped to the southern port city of Aden the following month. The Houthis and security forces loyal to Mr Saleh then attempted to take control of the entire country, forcing Mr Hadi to flee abroad in March 2015.
Alarmed by the rise of a group they believed to be backed militarily by regional Shia power Iran, Saudi Arabia and eight other mostly Sunni Arab states began an air campaign aimed at restoring Mr Hadi’s government. The coalition received logistical and intelligence support from the US, UK and France. After more than a year-and-a-half of fighting, no side appears close to a decisive military victory.
Jihadist militants from al-Qaeda in the Arabian Peninsula (AQAP) and rival affiliates of so-called Islamic State (IS) have meanwhile taken advantage of the chaos by seizing territory in the south and stepping up their attacks, notably in government-controlled Aden.
Civilians have borne the brunt of the fighting and repeatedly been the victims of what activists have described as serious violations of international law by all parties. By early October, at least 4,125 civilians had been killed and 7,207 others injured, according to the United Nations. With just under half of the population under the age of 18, children constituted a third of all civilian deaths during the first year of the conflict.
The destruction of civilian infrastructure and restrictions on food and fuel imports have also led to 21 million people being deprived of life-sustaining commodities and basic services. The UN says 3.1 million Yemenis are internally displaced, while 14 million people are suffering from food insecurity and 370,000 children under the age of five are at risk of starving to death. More than 1,900 of the country’s 3,500 health facilities are also currently either not functioning or partially functioning, leaving half the population without adequate healthcare.”
Many have accused the US of Aiding Saudi Arabi in War Crimes in Yemen
According to Vox article, “The US may be aiding war crimes in Yemen“:
“The US is giving direct military support to the Saudi campaign, including providing aerial refueling of the Saudi warplanes that have hit schools, hospitals, and other civilian targets across the country. That’s raising serious questions about whether the US is complicit in potential Saudi war crimes.
The fight in Yemen pits the Saudi-led coalition — which also includes aircraft from the United Arab Emirates and other Gulf powers — against Houthi rebels backed by Iran. The Houthis ousted the US- and Saudi-backed Yemeni government of Abdrabbuh Mansur al-Hadi last year. Saudi Arabia, which sees Houthis as proxies of Iran, its biggest regional rival, responded with a military campaign called Decisive Storm that’s designed to oust the Houthis and return Hadi to power.
It’s not going as planned. The Saudi-led coalition has killed large numbers of Houthi fighters but has also suffered significant civilian casualties of its own. More than 20 months later, the Houthis are still in control of much of the country, including the capital of Sana’a. The fighting shows no signs of stopping.
Neither, unfortunately, does the rising human cost of the war. According to the United Nations and other outside monitors, the fighting has killed 10,000 and left 370,000 children malnourished and 10,000 more dead of preventable disease. Nearly 3 million Yemenis have been pushed out of their homes.
The US has condemned the civilian death toll and urged the Saudis to exert more restraint. Washington also plays no role in helping determine which targets the Saudis bomb. Still, there is no question that American support — the US has flown more than 1,600 refueling missions, or roughly two a day, as of late November — has made it easier for Saudi Arabia to bomb the country, and that it has directly contributed to Yemen’s suffering.”
Human Rights Watch: #StopArmingSaudi – Stop Arming Saudi Arabia
Campaign Against Arms Trade (CAAT): Stop Arming Saudi: Yemen (UK)