As the United States, Canada and Mexico kick off negotiations on Wednesday to modernise the North American Free Trade Agreement, the biggest uncertainty is whether a deal can pass US President Donald Trump's "America First" test.
Trump has blamed Nafta for shuttering US factories and sending US jobs to low-wage Mexico. The test will be whether negotiators can prove that a new Nafta agreement can alter that course.
The call from the US business community in the run-up to the talks has been "do no harm" amid concerns that a new agreement will unravel a complex North American network of manufacturing suppliers built around Nafta.
Trump, who made trade a centrepiece of his presidential campaign as he promised to reinvigorate the manufacturing sector, pulled the US out of the Trans Pacific Partnership trade pact shortly after taking office in January. But he has since backed off other trade threats, including declaring China a currency manipulator and tearing up Nafta, which he regularly calls a disaster.
US-Canada-Mexico trade has quadrupled since Nafta took effect in 1994, surpassing $1tn in 2015.
Nafta renegotiations will be a major test of Trump's ability to meet his campaign promises to restore US manufacturing jobs. Although he has inherited a strong economy that has added 1.29 million jobs this year, his promises of an ambitious legislative agenda have been derailed by the failure of a healthcare bill and the lack of a detailed plan for tax reform.
An 'ambitious' first round
This week's talks will be led by US Trade Representative Robert Lighthizer, Canadian Foreign Minister Chrystia Freeland and Mexican Economy Minister Ildefonso Guajardo. Each side is expected to make remarks at the start of the talks being held at a historic Washington hotel.
The first round of meetings, which is expected to last until Sunday, will largely be administrative and focus on merging proposed texts from all three sides, according to a senior US trade official, speaking to reporters on the eve of the talks.
The official said the sides were aiming for an "ambitious" first round of talks.
The US has made lowering the $64bn US trade deficit with Mexico its top priority in the Nafta talks, although trade experts argue that such a goal will not be achieved through trade deals but rather by boosting savings.
Canada's Freeland suggested on Monday that Canada would walk away from the talks if the US insisted on scrapping the mechanism.
Mexico has said its Nafta goals are free access for goods and services, greater labour market integration and a strengthening of energy security.