It’s now been more than a week since a Russian passenger jet plummeted to the Earth at 300 miles per hour in the Sinai Peninsula and to be sure, we’ve made no secret of our suspicions that an explosion was the likely culprit.

Of course you needn’t be an Egyptian forensics expert or some kind of flight safety guru to come to the conclusion that a “technical failure” probably wasn’t responsible for the what happened. Sadly, the fact that body parts were littered in an 8 kilometer radius supports the contention that the aircraft did indeed explode and over the course of the last several days, both Washington and London both said that intercepted “chatter” points to ISIS.

And then there’s the fact that IS Sinai insists they “destroyed” the plane.

On Sunday, we got still more evidence that an explosive device may have been planted on the flight. Reuters, citing sources familiar with the black box investigation, now says officials are “90% sure” that a bomb was responsible. Here’s more:

Investigators of the Russian plane crash in Egypt are "90 percent sure" the noise heard in the final second of a cockpit recording was an explosion caused by a bomb, a member of the investigation team told Reuters on Sunday. His comments reflect a higher degree of certainty about the cause of the crash than the investigation committee has so far declared in public. Lead investigator Ayman al-Muqaddam announced on Saturday that the plane appeared to have broken up in mid-air while it was being flown on auto-pilot, and that a noise had been heard in the last second of the cockpit recording. But he said it was too soon to draw conclusions about why the plane crashed. Asked to explain the remaining 10 percent margin of doubt, the investigator declined to elaborate, but Muqaddam cited other possibilities on Saturday including a fuel explosion, metal fatigue in the plane or lithium batteries overheating.

So, it’s either the metal “expired” (so to speak), some batteries overheated, or the plane was blown up by terrorists. You can draw your own conclusions there.

If you, like David Cameron and US intelligence officials, do indeed believe that an “explosive device” was on board, then the next question to ask is how it got there. According to Sharm El Sheikh workers who spoke with WSJ, there’s speculation this was an inside job:

Airport workers here say they have faced intensive questioning in recent days from Egypt’s internal security agency, a sign the government is now exploring the prospect that airport insiders might have facilitated a terror attack that brought down the Russian plane that crashed last weekend. The workers say officials from Egypt’s Ministry of Interior, the internal security agency, have questioned them about their actions and whereabouts on Oct. 31, the day the plane crashed in the Sinai Peninsula, killing all 224 people on board. At the same time, Egypt’s military has assigned guards for airplanes staying overnight on the tarmac of Sharm El Sheikh International Airport, according to workers, as international carriers resumed flights this weekend to ferry stranded vacationers back home. “Normally, policemen are not allowed on the tarmac,” said a person familiar with the security arrangements. “Recently, they’re being asked to spend nights beneath jets.” In the Egyptian civil aviation ministry’s first public briefing since last weekend’s crash, agency chief Ayman Al Moqadem confirmed that there had been a mysterious sound heard on the final second of the cockpit recorder, but shed no light on what the pilots discussed during the 23 minutes after takeoff and before Metrojet Flight 9268 went silent.

To be sure, none of this is particularly surprising given everything we've learned over the past several days and at a certain point, one has to ask how many officials need to come out and confirm that this was indeed a bomb before someone finally delivers definitive proof, but regardless of whether the story is starting to get repetitive, it still has far-reaching implications - and not just for Russia's campaign against Islamic extremists. Here's Bloomberg:

“If this turns out to be a device planted by an ISIL operative or by somebody inspired by ISIL, then clearly we will have to look again at the level of security we expect to see in airports in areas where ISIL is active,” U.K. Foreign Secretary Philip Hammond told BBC Television’s Andrew Marr show on Sunday. Emirates airline, ranked world No. 1 by international traffic, is already looking at its security procedures in anticipation of tighter rules, President Tim Clark told reporters in Dubai on Sunday. “As we speak, we’re reviewing our procedures in terms of security and ramp handling and access to our aircraft,” Clark said. “We have 22 cities in Africa, multiple cities in west Asia -- India, Pakistan, et cetera -- all of these will have to be reviewed to make sure we’re as safe as we can be.” Britain banned commercial flights to and from Sharm el-Sheikh on the Red Sea in the wake of the crash, leaving thousands of vacationers stranded. Other countries, including Russia, followed and travel warnings ensued with Norway, Finland and Denmark all advising against all non-essential trips. Hammond said those trying to get home on unscheduled flights face delays of two to three days at most. Egypt’s benchmark EGX 30 Index of stocks slumped 2.6 percent at the close in Cairo, the most in two months.

In short, this is likely to cause a global rethink of airline security and importantly, this is a veritable disaster for an Egyptian tourism industry which was still stinging from a September "incident" that saw the military accidentally engage a group of Mexicans having a barbecue after mistaking them for ISIS.

It will be interesting to watch the Egyptian economy over next six or so months because frankly, the above suggests Cairo could be in for a bumpy ride.

Finally, note that the al-Sisi government recently signed new legislation widening Cairo's surveillance authority and the President isn't exactly known for having a sterling record on human rights (he's a Mubarak disciple after all). If this ends up hobbling the economy, expect al-Sisi to crack down, setting the stage for more of the same in terms of social unrest, coups, and counter-coups.