Edit actually it was that you missed off the last bracket, I think.
In any case, the Yemen civil war is hardly just between two parties, it’s a tangled web of proxies. There are actually many allies who are technically fighting against one another through their proxies.
The US & Ansar Allah have been warring for nearly a decade now, regardless of whether the US has formally declared it so: https://en.wikipedia.org/wiki/Yemeni_civil_war_(2014–present)
The brackets broke the link: https://en.wikipedia.org/wiki/Yemeni_civil_war_(2014–present)
Edit actually it was that you missed off the last bracket, I think.
In any case, the Yemen civil war is hardly just between two parties, it’s a tangled web of proxies. There are actually many allies who are technically fighting against one another through their proxies.