Quartz, before I dig into your cites, here is your precise claim:
And your cites for this are…
Before even clicking on the link, that’s already a significant climbdown. “Brexit could cause World War III” is a very extreme claim. “Brexit could cause war” is a fairly reasonable statement predicated on the fairly young strife in Northern Ireland, and how that might be reinflamed by Brexit (among other things). This is not some random whackdoodle theory; this is a real concern. Google is your friend; here’s just one example from the Independent.
Now, looking at your link, I see your source is The Mirror. Not off to a great start, are we? But okay, what does the article say?
Introduced by Labour ex-Foreign Secretary David Miliband at the British Museum in London, he said: "Can we be so sure peace and stability on our continent are assured beyond any shadow of doubt? Is that a risk worth taking?
“I would never be so rash to make that assumption.”
Whoops, that’s another step down in the hyperbole. This statement is controversial, but it isn’t stupid. At least in my (German) high school classes, The European Union was credited in a major way with keeping the peace between European powers. This is not an uncontroversial view of history, but it’s hardly insane to posit that one of the EU’s largest nations leaving the EU (led by a ship of [del]fools[/del] insane racist cretins) might lead to upheavals and instability. And hey, what’s this, from your cite:
“No, I don’t believe that leaving the EU would cause World War Three to break out on the European continent.”
That quote is from Boris Johnson, who seemed quite eager to put words in Mr. Cameron’s mouth. Which may explain how you got this so wrong.
Again, in this interview, we have people putting words into Cameron’s mouth, and Cameron responding to the hyperbole in an entirely measured, reasonable way. Indeed, Cameron challenges him on where he said it would lead to World War 3, and Faisal Islam couldn’t. It’s 2 minutes out of a 57 minute interview, snipped out of context by a leave advocate trying to make David Cameron look silly.
So both of your cites are David Cameron, and neither really supports your point about Remain hysterics. But even if they weren’t wildly distorted… Okay, there’s one person of note - a person of note who resigned immediately after the vote. Who else?