That would be true if applications ran on only one computer at a time. But nowadays applications run across many computers - sometimes tens of thousands of them. These applications don&#x27;t need the operating system to protect processes from each other, because they are not running on the same computer.<p>Now that hypervisors are a mature commodity, this model is practical at smaller scale too: instead of running in separate physical computers, process run in separate virtual computers.<p>In short: unikernels make way more sense if you zoom out and think of your entire swarm of computers as a single computer.