You are not the only one thinking that.
From the ABC News:
National security experts say an armed attack on a Navy base in Darwin could have been an inside job by someone with military training.
A man wearing military-style clothing broke into the HMAS Coonawarra base, near Darwin's central business district in the early hours of Thursday morning.
He overpowered a crewman on board the Armidale-class patrol boat Bathurst, stealing a dozen pistols and two pump-action shotguns from the ship's armoury.
Police are continuing to hunt for the man, and are not ruling out that someone connected to the Defence Force was involved.
Australia Defence Association executive director Neil James told ABC News 24 the attack might have been an inside job.
"The police suspect it might be someone with inside knowledge," he said.
"Certainly in the cases where military armouries have been robbed over the last few decades that's often been the case."
"The weapons have to remain onboard the vessel because the vessel might have to be scrambled for sea at very short notice and so there is a limit to the steps you can take to prevent something this like this happening."
Obias Feakin from the Australian Strategic Policy Institute says the theft would have required considerable planning.
"This one individual was able to get on board a vessel and understand where the particular weaponry was on board," he said.
"That would indicate a degree of knowledge in understanding these types of ships.
"The fact that they were able to tie up and apprehend a member of the Navy, again [means it was] a well-trained individual."
"If he made his way in by sea then that would indicate that perhaps there's a slight Achilles heel in terms of that part of the security operation up there in Darwin," he said.
The Chief of Navy Vice Admiral Ray Griggs has ordered an investigation into security on all Australian Navy ships and bases.
Stable doors and horses bolting come to mind!