I think you're underplaying the threat.
The combination of wide-area surveillance, close-in target shadowing, and terminal guidance has allowed the Houthis to achieve some impressive feats of marksmanship, such as an apparent near-miss on a U.S. aircraft carrier and a number of hits or very close misses by ASBMs on ships approximately 150-200 kilometers from launch points.
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By some accounts, an ASBM or other missile arrived at a very shallow trajectory, with minimal warning, without a chance for interception, and splashing down around 200 meters from the Eisenhower. Details gathered from interviews with Yemen-focused U.S. and U.K. intelligence officers for this study. Names of interviewees, and dates and places of interviews withheld at interviewees' request. The Houthis propagandized the carrier's departure. See "America's withdrawal from the Red Sea confirms the fall of the myth of Washington's great power," Sabant – Saba Agency, May 1, 2024
The enemy is learning, and adapting. We are too of course, but it's a case of diminishing returns on our end as our enemies continue to slowly close the gap. Our multi-layered defense systems are remarkable, but not perfect. Iran got 5% of their stuff to break through into Tel Aviv, the most well defended city in the world when it comes to missile defense. That's not inconsequential, and Iran didn't fire everything they have. It's not that I think Iran can win, because even they know they can't win... they still haven't fully replenished all the missiles they used last year even with China circumventing sanctions and delivering raw materials. I just don't think we're as invulnerable as your language suggests.