Here's something interesting. I don't know if it was mentioned before, but there is a book "Scimitar SL-2" by Patrick Robinson. It's just another Tom Clancy or Clive Cussler like" novel. But here's the interesting part. Let me just write a blurb from back cover...

"A massive tsunami triggered by a terrifying weapon in the hands of a madman ...

Scimitar SL-2

He calls himself Ravi Rashood, a former SAS officer who currently masterminds one of the world's most virulent terrorist organizations. An elusive madman dedicated to the annihilation of the West, he now possesses the means to accomplish his nightmarish goal: a nuclear-tipped cruise missile named after the avenging sword of the Muslim warrior Saladin.

Fired into the crater of the most dangerous volcano in the Canary Islands, the Scimitar SL-2 will trigger a sequence of geophysical events that will create a mega-tsunami the likes of which have not been seen in modern times. It would pound the southern coastlines of Europe and flatten the entire eastern seaboard of the United States.

U.S. Admiral and retired National Security Adviser Arnold Morgan knows that Rashood must be stopped, but finding him won't be easy. The killer and his terrorist crew are hiding aboard a virtually undetectable submarine somewhere in the vast depths of the ocean. But for Morgan and the U.S. Navy, there is no choice -- because time is an enemy ... and the only alternative is the first Atlantic mega-tsunami in 4,000 years."

Few excerpts from a book...

"Professor Landon’s closing focused on the new potential landslide on the southwest coast of La Palma, the northwesternmost of the Canary Islands. (Jutting out from deep Atlantic waters, La Palma stands 375 miles off the southern coast of Morocco.)
The fact was, he explained, that a gigantic hunk of volcanic rock, several miles long and set on a searing fault line in the earth’s crust, had slipped in the last forty or fifty years, maybe twelve feet down the steep cliff, detaching from the west flank. And somewhere behind this colossal, unstable chunk of rock lay, potentially, the simmering core of the mighty volcano of Cumbre Vieja.
“That lets rip, and the lot goes,” Professor Landon asserted, brightly. “It’d send a staggeringly large rock, several cubic miles of it, crashing off the west flank of the volcano, straight into the Atlantic at more than 200 mph, and surging along the ocean floor, at maybe 400 mph. I’m talking about one of the largest landslides in the past million years. Actually I’m talking about the total collapse of the southwest section of La Palma.”
The packed audience of ex–Military and Naval Officers, scientists, academics, and scions of ancient landed families, which had always shown an interest in such scientific matters, had listened, wide-eyed, as the Professor explained the establishment of a gigantic column of waves, ascending from the seabed to the surface, driving forward to reach speeds of 500 mph, and rising to a height of maybe 200 feet into the air as they arrived in shallow coastal waters.
Landon went on to describe how the monstrous tidal surge would wipe out large hunks of coastal southern England, Spain, and West Africa. And then, within nine hours from the moment of the rock’s impact on the surface of the Atlantic off southwestern La Palma, the massive wall of water would travel across the Atlantic and obliterate the entire East Coast of the United States.
“If Cumbre Vieja blows, this will happen,” he confirmed. “A rare and terrible mega-tsunami. Scientific research has estimated a number of intense waves, still perhaps 150 feet high, crashing into the restricted seaways off lower Manhattan, and then flattening the Wall Street area of New York with its very first sweep.
“The opening tidal wave would suck the debris out of the streets and flatten the ground before the next one of the wave series hit, demolishing buildings up to possibly fifteen blocks from the waterfront. And these giant waves — each one more than 100 feet high — would keep coming, progressively, until all of New York City was levelled.
“The biggest tsunami in recorded history. And all because of a single volcano.”

....

“I’ve read up on the subject, and the truth is obvious. He hits the Cumbre Vieja volcano, that mega-tsunami will happen. And that’s likely to be sayonara New York…”
“Of course I see your problem. You are obliged to buy a little time by making moves in the Middle East to look as if you are leaving. But what you are really doing is getting a great battle fleet into operation in the Atlantic in order to find and destroy the submarine, or intercept the missile as it flies into La Palma?”
“How the hell do you know they’re in a submarine?”
“Please, Arnold, give us some credit. We know about the missing Barracuda s. We know you found one of them, already scuttled. And we know the other one is on the loose. There is plainly no other way to hit the volcano except with a submarine-launched missile. An aircraft is out of the question, so is a surface ship, and a blast from the mainland of black North Africa would be to invite instant detection by the U.S. satellites.
“No, Arnold. They have informed you what they plan to do. And quite obviously, they are going to launch their missile attack from a submarine creeping around, deep, somewhere in the North Atlantic, somewhere off the coast of Africa. And since that Barracuda is the only suspect… the rest is academic.”


And here's the punch-line...


"General Rashood and the Commander in Chief of the Iranian Navy, Adm. Mohammed Badr, were trying to decide whether another communication to Washington was necessary. Did the Americans think that the Hamas high command would not carry out their threat because world opinion would most likely turn against them?
In which case, someone needed to put the Pentagon right. Sometime on October 9, young Ben Badr would fire those two Scimitar SL-2s straight at the Cumbre Vieja, no ifs, ands, or buts.
Ravi was working on a draft, and he was nearly through with it. The wording was as follows…

To: The Chairman of the Joint Chiefs, The Pentagon, Washington, D.C.:

There is nothing you can do to stop us now. We regret that you have ignored our instructions. You will still be under water when our brothers in Palestine rise again."