Donald Trump claimed the Republican nomination on the strength of a candidacy opposed to free trade. Faced with the insurgent candidacy of Bernie Sanders, former Secretary of State Hillary Clinton, shifted her positions, most notably now opposing the Trans-Pacific Partnership (TPP).

Business leaders face a dilemma: what should they do when both candidates are spouting positions that are directly contrary to their interests? Thus far, they are remaining silent, assuming they can recover after the election through an inside game. This may be a historic misjudgment on their part.

For the past quarter-century, global trade has been the engine of American business growth and its dominance of numerous global markets. Rather than remain silent, business leaders should offer rebuttals, speaking out now to provide policy solutions for the new administration. Let’s look at some of the most vital areas:

Free Trade

Trade has created millions of jobs in the U.S., far more than jobs lost. The U.S. Chamber of Commerce points out that NAFTA alone created 5 million jobs. Other experts warn that the massive 45% tariff on Chinese imports that Trump proposes would cause a trade war with China striking back with excessive tariffs of its own or banning imports from the U.S. altogether. High tariffs on Chinese and Mexican goods would raise prices for U.S. consumers, hurting lower-incomes families who shop at Walmart (WMT) or Target (TGT).

As trade has opened up, American companies dominate the list of the world’s most valuable companies. At the end of 2015, 579 of the 2,000 largest companies are U.S.-based. Abandoning free trade risks both jobs and economic value creation.

Job Creation

Technology and productivity gains, not trade, have held down job creation during the last decade. For example, it takes only 10% as many workers to build a Ford as it did 20 years ago, thanks to automation. Meanwhile, the U.S. auto industry is booming, producing record numbers of vehicles as the Big Three have regained competitiveness with foreign makers. Communications advances have made global outsourcing easier for large U.S. firms who can offshore lower-value jobs, such as customer care or software QA, to cost-effective locations. At Medtronic, we found every factory worker added in our overseas plants created three new jobs in the U.S. in R&D, manufacturing processes, marketing and sales. Silicon Valley companies have an even greater ratio.

Watch Donald Trump’s speech on trade:

Corporate Taxes

U.S.-based companies hold more than $2 trillion of cash overseas, because they refuse to pay both overseas taxes and the higher U.S. corporate tax rate of 35% to repatriate the funds. Meanwhile, this money is not being reinvested in the United States. This dysfunctional system makes U.S. companies more valuable to foreign acquirers than their U.S. shareholders, and has caused several companies to relocate their legal headquarters outside of the U.S.

The U.S. could fix this problem by reducing corporate tax rates while eliminating loopholes in tax policy. Short-term, the government should create a foreign income tax repatriation holiday of taxes at 10-12% for companies with specific plans to reinvest the savings in the U.S. My Harvard Business School colleagues, Michael Porter and Jan Rivkin, would go a step further with territorial taxes that tax profits where they are earned. This would eliminate double-taxation of profits, thereby enabling American companies to redeploy capital in smart investments at home. At the same time, doubling investment tax credits for new tangible assets and increased research and development would strengthen the technology advantage for America’s global companies.

Education

While unemployment has dropped 50% since President Obama took office, millions of Americans that lost their jobs in the 2008-09 recession lack the skills for today’s positions. The failure of the U.S. Congress to authorize funds for job retraining after the 2008-09 recession has contributed to these problems. Our K-12 and higher education systems also do not produce the talent that innovative companies need to grow.

In addition to job retraining, the U.S. needs to strengthen its vocational and technical education system, encouraging more high school students to consider these alternatives. Some companies, such as AT&T, are partnering with schools like Georgia Tech to offer specialized online training. The U.S. could do much more to ensure that educational institutions provide the mentoring, faculty and facilities that produce the types of workers companies clamor to hire.

Isolationism Won’t Make America Great

Concerns about wage stagnation among U.S. workers are legitimate, but they are only part of the broader economic story. Suppressing free trade will harm these workers much more than the companies who can access overseas labor.

Corporate leaders need to take on the importance of making American companies fully competitive in global markets. A pro-growth agenda—one that educates workers for the future, incentivizes investment and allocates resources effectively through trade—is a far better way to navigate the next decade than practicing the politics of isolationism.

Business leaders have an important case to make. There are only two months left to speak out.

Bill George is Senior Fellow at Harvard Business School, former Chair & CEO of Medtronic and author of Discover Your True North.