The Houthis have grown into an international security threat that increasingly operates beyond Tehran's control, according to Tim Lenderking, who served as the U.S. special envoy for Yemen from 2021 to 2025. Speaking at a briefing hosted by the Middle East Institute, Lenderking said the group's expanding arsenal and self-sufficient supply networks have turned what began as a regional insurgency into a danger that reaches well beyond Yemen's borders.
His warning came as Saudi officials disclosed the toll from a wave of attacks on the kingdom's infrastructure. Turki al-Maliki, spokesperson for the Saudi-led coalition in Yemen, said strikes on King Khalid International Airport in Riyadh killed 17 people and injured 333 others between Oct. 7 and Oct. 11. The Oct. 10 attack alone involved 10 drones, missiles and other projectiles, he said at a news conference in Riyadh, adding that the airport had been targeted 20 times since Oct. 1.
Lenderking, who was posted to Saudi Arabia from 2013 to 2016, said Saudi officials had warned American leaders more than a decade ago that the Houthis would become a major threat. At the time, he recalled, the group was quietly building its capabilities while promoting its claim to lead Yemen as a messianic movement from the country's north. That prediction, he said, has now materialized.
The Houthis emerged as a religious and political movement in Yemen in the 1990s, but their relationship with Iran developed into a military partnership after 2014, when Tehran expanded assistance and training during Yemen's civil war. Lenderking said that support helped the group become the force it is today, but he argued the relationship has changed. «The Houthis don't really need the Iranians anymore,» he said, while describing the ties as still important.
Over time, Lenderking said, the group developed what he called a homegrown indigenous capability, capitalizing on divisions across the Gulf region. He pointed to the precision of the Riyadh airport attack as evidence of its progress. «They can hit things better. Now, they are hitting Terminal Four of Riyadh Airport, very specifically. It's a clear and very present danger,» he said.
The Houthis reportedly launched multiple drones followed by cruise and ballistic missiles that traveled more than 620 miles to Riyadh, prompting an investigation into possible Saudi air defense failures. Saudi forces intercepted two more ballistic missiles targeting Riyadh on Monday. On Tuesday, a Houthi strike damaged Aramco's headquarters in Dhahran, sparking a fire that spread across several floors.
Lenderking said the group has built extensive weapons supply chains, smuggling networks and domestic financing operations that allow it to sustain attacks without relying solely on Tehran. It obtains supplies through the open market and commercial exchanges, he said, and moves material through a smuggling network that runs from large boats to small boats and eventually on pack animals and people's backs.
Financing comes from black-market oil sales, taxation and extortion, according to Lenderking. He said the Houthis tax people in areas they control and force families to provide a son to fight on the front lines. «They have had support from Iran over the years, so they have money in the bank from that,» he said.
The group's expanding arsenal has also raised concerns about potential Chinese involvement in its weapons supply networks. Yemen's government has accused the rebels of seeking Chinese components for medium-range ballistic missiles, a charge that points to worries about their access to advanced military technology.
Asked whether the United States would defend Saudi Arabia against further attacks, President Donald Trump said, «You'll find out soon.» The remark left open the question of how far Washington might be drawn into a broader regional conflict as Riyadh seeks American assistance.
Lenderking said the Houthis' reach now extends around the region, including the northern stretches of the Red Sea. Because the group controls Yemen's west coast, he argued, the problem is no longer confined to one country. «It's an international problem now,» he said.