Wall Street thinks stocks will rise in 2017 — What could go wrong?

Wall Street’s rally could be derailed by renewed worries about President-elect Donald Trump’s policies, a resurgent dollar or potential wild-card events like cyber attacks or a trade war, investors say as they look to 2017.

Stocks are at record highs on optimism Trump will boost the economy, and strategists in a recent Reuters poll expect more gains next year. But they also worry about what could derail the market as a surprising 2016 wraps up and an uncertain 2017 awaits. Here are some potential roadblocks to more gains:

TRUMP FALLS SHORT

Many strategists’ top worry is that Trump’s efforts to boost the US economy will be diluted or delayed by a Republican-controlled Congress reluctant to widen the budget deficit. Trump’s promises to ease regulations, cut taxes and boost infrastructure spending have spurred sharp gains in shares of banks, health care and construction-related companies. “As bold as people think these policy changes are going to be, maybe they get watered down,” warned Bob Doll, chief equity strategist at Nuveen Asset Management in Princeton, New Jersey.

TRUMP AND TRADE

Underscoring investor worries about Trump’s threats to renegotiate trade deals, retail shares fell 3.5 percent on December 22 on reports he is considering import tariffs as high as 10 percent. A day earlier, Trump named Peter Navarro, an economist who has urged a hard line on trade with China, to head a newly formed White House National Trade Council. Tariffs on goods from countries like China and Mexico would bump up costs on imported goods for U.S. consumers.

THE DOLLAR CRIMPS EARNINGS

Further strength in the dollar, which has gained nearly 5 percent since the election, could hobble sales of US multinationals. “Companies are saying, ‘You know, we’ve got this higher dollar that’s making our business overseas a little more difficult,” Doll said. A year-long US profit recession has just ended, but earnings growth needs to pick up or stocks will get too expensive. The S&P 500 is now trading at nearly 18 times forward earnings versus a long-term average of about 15, Thomson Reuters data shows.

FED GETS REALLY AGGRESSIVE

Stocks racked up big losses earlier in December after the Fed signaled three rate hikes are likely in 2017. While a stronger economy boosts stocks, higher rates can hit spending. “One risk would be the Fed being a little overzealous and maybe bringing rates up quicker than what makes sense,” said Daniel Morgan, portfolio manager at Synovus Trust in Atlanta, Georgia.

POPULISTS DEAL BLOW TO EU

Anti-establishment candidates are on strong footings ahead of spring elections in the Netherlands and France, and victories for them could strike a critical blow to a European Union already weakened by Britain’s vote to leave. Ahead of the Netherlands election in March, surveys point to strong gains for the euro-skeptic Freedom Party. In France, far-right National Front leader Marine Le Pen’s popularity recently reached 27 percent ahead of a May election.

“There is still an overwhelming lack of recognition of the power of populist movements,” said Brad McMillan, chief investment officer for Commonwealth Financial Network.