Sadly, it had to be this way. From the moment on Friday that Cricket Australia was warned by the government of a threat to Australian interests in Bangladesh, the cancellation of the tour seemed likely. From the moment on Monday that an Italian charity worker was shot dead in Dhaka and Islamic State reportedly claimed responsibility, it was certain. CA had no option but to abandon their tour.

It is sad for Bangladesh cricket, for the players and the fans. This should have been a big series for Bangladesh, their first Tests against Australia in nine years. Their one-day form this year is strong, and in their home conditions this looked set to be a competitive series against a raw, regenerating Australian side. It should have been an entertaining contest.

It is sad for Australian cricket. A young squad was to have its first taste of cricket in Asia under new captain Steven Smith. New faces like Cameron Bancroft and Andrew Fekete now do not get that opportunity. The challenge of playing a Bangladesh team on the rise, of testing themselves in unfamiliar conditions - that is gone for now.

Most of all it is sad for the sport itself that once again factors outside of cricket could force a tour to be abandoned. Bangladesh has not previously been viewed as seriously unsafe; nobody wants it to become the new Pakistan. Nobody wants to bow to the threat of violence. But a government's security agencies do not publish these travel warnings on a whim.

"Put yourself in the position of Cricket Australia. Is there a bigger, more visible "Australian interest" in Bangladesh than a touring cricket team?"

To the citizens of Bangladesh, this may well feel like an insult. That is natural, and completely understandable. The past few months in Bangladesh have been peaceful, certainly more so than in 2013-14, when political violence surrounding the country's general election caused concerns in the lead-up to the World T20, an event that ultimately went off without a hitch.

But this is not about domestic political violence. It is not about the feeling of safety and security that Bangladeshis feel in their own country. This is about the Australian government warning its citizens of "reliable information to suggest that militants may be planning to target Australian interests in Bangladesh". Not just "western interests" generally, but "Australian interests" specifically.

That is why it is irrelevant that other teams such as South Africa, India and Pakistan have toured Bangladesh this year without incident. The warning was published on the Australian government's Smartraveller website only on Friday. That is why it is irrelevant that Australia have toured Bangladesh safely in the past, including for last year's World T20. This warning is new.

That is also why this cannot be compared to touring India after terrorist attacks in 2008, or touring England after the 2005 London bombings. Those were not attacks directed specifically at Australians. The wording of this latest warning - "Australian interests in Bangladesh" - is worryingly unambiguous. No such advice exists for other countries in south Asia.

None of us outside the intelligence community can know how or why the government came upon this information, which it calls "reliable". We are not privy to that background, and for that reason we have no option but to take the advice seriously. Cricket Australia had no option but to do so either in spite of the high level of security offered by Bangladesh's government and cricket board.

Bangladesh fans cheer their team on AFP

Put yourself in the position of Cricket Australia. Your government contacted you directly on Friday to warn you that its travel advice was about to change, that it believed militants may be planning to target Australian interests in Bangladesh. Your team was due to fly there on Monday. Is there a bigger, more visible "Australian interest" in Bangladesh than a touring cricket team?

That is not to say there was any specific threat to the Australian squad. But could Cricket Australia take that chance? After the tragedy of the attack on the Sri Lankan team in Pakistan in 2009, could Cricket Australia take such a risk in the face of such recent, specific advice from its own government? Sadly, it could not. It had no option but to abandon the tour, for no security is truly foolproof.

The death of the Italian man in Dhaka on Monday led to further security warnings, including the Australian government advising its staff in Bangladesh to travel only by vehicle. Also on Monday, the US State Department stated that there was "reliable new information to suggest that militants may be planning to target Australian interests in Bangladesh."

What this means for Bangladesh in the longer term is unclear. Naturally, it is to be hoped that future tours there can go ahead, but that will depend on the security advice at the time. For now, the security advice is clear. That is why Cricket Australia's decision to abandon their tour was sad but inevitable. And sensible.