Despite governments' pursuit of free trade treaties, these jurisdictions have stuck to policies, which guarantee heavy involvement of local suppliers in government projects - including mandated use of local steel.

And in Australia, Victoria leads the way with local content policies for government contracts.

Western Australia also favours local suppliers, working with major resource companies to include local content, with the WA Department of Commerce reporting openly on the percentage of local content in major private sector projects.

The New South Wales government is coming under pressure to consider domestic steel quotas after BlueScope threatened it may have to close the Port Kembla steelworks.

But Australia may soon enter another treaty restricting the government's ability to choose local suppliers.

In Canada, major government projects will often include a minimum local content quota, Canadian union economist Jim Stanford said.

"The government will then negotiate with specific suppliers regarding how those benchmark levels are going to be met," he said.

Government procurement in the US is often ruled by the Buy American Act, which since 1933 has mandated "substantially or all" domestic content for any government-funded project.

Highway and rail legislation demands 100 per cent US-manufactured iron and steel if a project is to receive government funds.

In 2014 the Water Resources Reform and Development Act ruled that all waste water and water infrastructure projects could only get government funding if they used US iron and steel.

In Australia, government "buy local" rules have often stopped at a local content declaration, rather than legislation.

In Victoria, the government has a policy that the current replacement of 50 level crossings must use 100 per cent Australian steel.

And when contracting for train and tram rolling stock construction, the Andrews Labor Government says that 50 per cent of manufacturing must be done locally.

It is not clear whether this is law or a just a target. And the Victorian quota has sometimes included the whole "value-added" cost of an asset - which means maintenance and training for a tram's lifetime could be included in the "local content" count.

Victoria's policies may be changing.

They are about to undergo a review, and Industry Minister Lily D'Ambrosio's office was this week unable to comprehensively detail how the local content policies work in that state.

The terms of reference for the review will be announced soon.