Good explanation of what happens when anchors land on internet cables and how the internet feeds conspiracy theories at The Economist Of cables and conspiracies:
The notion that something spookier than ships' anchors was to blame gained ground when Egypt's transport ministry said it had studied video footage of the sea lanes where the cables had been, and no ships had crossed the line of the breakage for 12 hours before and after the accident (the area is, in fact, off limits to shipping). Suspicion spread when yet another cable—between Qatar and the United Arab Emirates—went down on February 3rd. “Beyond the realm of coincidence!” said a user of ArabianBusiness.com.More on this here.
In fact, the fourth break was unsuspicious: the network was taken down by its operator because of a power failure. But by that time the conspiracists were in overdrive. Slashdot.org, a discussion board, said Iran had lost all internet access on February 1st. “A communications disruption can mean only one thing—invasion,” said bigdavex, quoting a line from a “Star Wars” film. Bloggers in Pakistan, having recovered from their disruption, returned with a vengeance. The broken cables, they said, forced a delay in the opening of an oil bourse in Tehran; this would have led, claimed pkpolitics.com, to the mass selling of dollars “which would have instantly crashed [the American] economy”. Marcus Salek of New World Order 101.com (nwo101.com) added that “President Putin ordered the Russian air force to take immediate action to protect the Russian nation's vital undersea cables.”
There is just one small problem: Iran's internet connectivity was never lost. Todd Underwood and Earl Zmijewski of Renesys, an internet-monitoring firm, reported that four-fifths of the 695 networks with connections in Iran were unaffected. Most of the other theories dissolve under analysis, too. Perhaps the American navy can bug fibre-optic cables but it's not clear how. A report for the European Parliament found in 2000 that “optical-fibre cables do not leak radio frequency signals and cannot be tapped using inductive loops. [Intelligence agencies] have spent a great deal of money on research into tapping optical fibres, reportedly with little success.”
It may be rare for several cables to go down in a week, but it can happen. Global Marine Systems, a firm that repairs marine cables, says more than 50 cables were cut or damaged in the Atlantic last year; big oceans are criss-crossed by so many cables that a single break has little impact. What was unusual about the damage in the Suez canal was that it took place at a point where two continents' traffic is borne along only three cables. More are being laid. For the moment, there is only one fair conclusion: the internet is vulnerable, in places, but getting more robust.