by JOSEPH TREVITHICK

On April 20, reports began to circulate that the U.S. Navy might be preparing to intercept an Iranian flotilla loaded with arms for Houthi fighters in Yemen.

But even if those ships make it through, Tehran might end up learning a lesson Washington has recently been forced to accept—millions of dollars in weapons won’t automatically buy a stable Yemen.

In February, the Shi’ite insurgents took over the capital Sana’a and quickly chased the internationally-recognized president Abd Rabbuh Mansur Hadi to the port city of Aden.

While a Saudi-led intervention aims to put Hadi back in power, the country appears to be fully embroiled in a civil war that now also includes Al Qaeda’s local affiliate as well as Islamic State.

“The devastating conflict in Yemen takes place against the backdrop of an existing humanitarian crisis that was already one of the largest and most complex in the world,” Johannes Van Der Klaauw, the Humanitarian Coordinator at the United Nations’ Office for the Coordination of Humanitarian Affairs, said in an April 17 press release.

And yet, between 2006 and 2014, Washington had delivered more than $500 million in arms and other military gear to try and help authorities keep the country together.

But even with these generous supplies, in the end Yemeni forces couldn’t hold off the Houthis.

The Pentagon’s deliveries included drones, helicopters, trucks, small arms, ammunition, radios and more, according to more than 70 documents War Is Boring obtained through the Freedom of Information Act.

The aid packages also paid for contractors to install various equipment, keep it all running and train Yemeni troops how to use their new toys.