Ryan Dawson covered this pretty well.
Basically to point it bluntly they wish to create a seaport at the Yemen seaport area under Saudi Occupation, continue causing issue to the rest of the country but capture a 25-mile "Danzig Corridor" scenario. And make the US go to war with Iran.
So by controlling this "Danzig Corridor" scenario just like in 1939. They wish to bypass shipping from the Straights of Hormuz and allow free-reign of US strikes on Iran.
Fortunately for us the Yemen aren't pushovers they are being backed by Iran and on top of that their Shabbab 3 Kornet's have been destroying dozens of Abrams tanks. Saudi's probably pissed away tens of millions of Russian and American equipment and who knows how many saudis died due to retarded muzzie tactics.
It's funny if they made a "schwerepunkit", a "main center of attack" with their tanks and forces a.l.a. Germany 1940, they'd probably have the port ages ago. But no they fight like retarded monkeys for a nation with so much money and oil and international flair. They sure like to fight like retards, so much for buying your way into military might. It's like Syria they deserve more international support and funny enough their military is scary trained and scary experienced.
Either way it's good the Yemen are holding the fort down and probably causing more issues and headaches to the jews and saudis cause if we get in a war with Iran it's bad for both sides.
Like it's been said "Operation Jade Helm" total failure was cancelled half-way as it was considered a suicide mission. And even a combined allied/coalition fleet Euro-American sea force would be destroyed by Iran.
According to a US Navy simulation even a combined fleet would be destroyed by Iran. Billions and Trillions lost and on top of that huge casualties. It'll be the worst defeat of a navy since the IJN in WW2.