If you’re a Chinese investor, you may as well toss a coin trying to work out the government’s attitude to whether it wants your money.

For much of this year, the government sought the high moral ground on Chinese investment by trumpeting its preferential trade agreement with China and attacking Labor and the unions as racist for raising concerns about the visa process that would apply to the importation of Chinese labour for large infrastructure projects. At the same time, it was running its own xenophobic campaign against Chinese investment in residential real estate, with then-treasurer Joe Hockey urging people to dob in foreign buyers and imposing layers of red tape on foreign investors.

Coupled with that was another xenophobic campaign, driven by the Nationals, against Chinese investment in agriculture. Foreign investment has been crucial to our rural sector since white settlement, but the Nationals played up the purported threat of Chinese investment to our “food security” (whatever that is). Long-term investment xenophobe Barnaby Joyce (again) breached cabinet solidarity this year to call for a blanket ban on any ownership of agricultural land by companies with links to foreign governments (read: Chinese companies). The Nationals were particularly exercised by the pending sale of the vast cattle station empire of S. Kidman and Co.

Step forward Treasurer Scott Morrison yesterday, to block the sale of the Kidman properties to Chinese interests, ostensibly on national security ground, because one of the properties is close to the Woomera weapons-testing range. Proximity to Woomera was also the basis for former Labor treasurer Wayne Swan rejecting Chinese firm Minmetals’ bid to acquire OZ Minerals in 2009.

It’s a different story for the Port of Darwin, though: despite a 99-year lease potentially giving Chinese government-linked Landbridge Group a window on US troop movements into and out of Darwin, the Defence Department expressed no concerns about the sale. A complicating factor is that the Northern Territory government isn’t required to obtain Commonwealth approval for the sale, but it’s hard to imagine the sale proceeding as is if Defence had expressed serious reservations about it. Morrison tried to blame Labor for the fact that the Foreign Investment Review Board didn’t rule on the sale, saying “the rules Labor had in place and that the Shadow Treasurer presided over did not permit this particular transaction to come under FIRB’s review.”

All Chris Bowen’s fault, apparently.

Confusingly, Trade Minister Andrew Robb contradicted the Treasurer, saying there’d been a nine-month consultation process involving FIRB and Defence. “There was strong support from all of those agencies,” according to Robb.

Confused? Welcome to the club. It’s hard to disagree with Labor’s defence spokesman Stephen Conroy, who spoke about a failure of internal government process.

The Americans were sufficiently underwhelmed by the deal for the President to complain about it to Turnbull; Turnbull shrugged that off with the observation that it was public knowledge and a wisecrack about the NT News. One imagines that a presidential rebuke and such an insouciant response would have been treated very differently by the media if it had happened to a Labor prime minister.

So let’s try to work out what Australia’s policy on Chinese investment is: it’s not welcome in agriculture or real estate, but criticism of it is xenophobic when it involves Chinese workers being brought to Australia; it poses national security concerns, except when it doesn’t, especially for projects that may — or may not — have been subjected a lengthy FIRB process.

Such is the apparently arbitrary nature of our position that one might almost reach for the much-abused phrase “sovereign risk”.

The only politician with clean hands in all this is Andrew Robb. Robb takes every opportunity he can to promote the virtues of foreign investment, whether its critics are on the left or the right. He’s equally happy going head-to-head with Alan Jones or the unions on the issue, because he believes foreign investment has always been crucial to Australia and will continue to be so.

The rest of his government, however, appears deeply confused. As are the Americans. And so, for that matter, are investors.