President Donald Trump's continued push to level the global playing field when it comes to trade has done little to disturb the relentless bull market in stocks.

But nothing lasts forever, and at some points investors will have to react if the tensions continue to escalate. By all indications, an acid test could come as early as week, with the administration poised to impose a range of new tariffs on $200 billion worth of Chinese goods.

Running a series of different scenarios in the U.S.-China conflict, experts at FactSet have come up with a worst-case trade war scenario, one in which most major economies would take a hit and the U.S., along with a few others, would see a bear market emerge.

"In the case of the escalating trade tensions between the U.S. and China, while financial markets still appear to be discounting the global impact of a trade war, our analysis shows that if/when the market does react, the effects will be widespread," Ian Hissey, vice president in FactSet's portfolio analytics group, said in a report last week.

Hissey modeled three scenarios: a base case where the dispute continues along its current path and tensions and tariffs gradually escalate; an optimistic result where the U.S. and China reach broad agreements on the future but the newly imposed tariffs remain, and a "conservative" case that involves "rapidly deteriorating" relations and a more profound impact.

In determining impact, Hissey used the market's Brexit reaction, following the 2016 vote that allowed the UK to leave the European Union, as a template.

He came up with results that showed stocks globally dropping between 8 percent and 17 percent, with markets in the U.S., Canada and Israel faring worst and Japan being the only overall winner. Hissey did not provide a time frame for how long the market move would take.