Pharmaceuticals have high fixed costs of R&D and low marginal costs. The first pill costs a billion dollars; the second costs 50 cents. That cost structure makes price discrimination—charging different customers different prices based on willingness to pay—common.

Price discrimination is why poorer countries get lower prices. Not because firms are charitable, but because a high price means poorer countries buy nothing, while any price above marginal cost is still profit. This type of price discrimination is good for poorer countries, good for pharma, and (indirectly) good for the United States: more profits mean more R&D and, over time, more drugs.

The political problem, however, is that Americans look abroad, see lower prices for branded drugs, and conclude that they’re being ripped off. Riding that grievance, Trump has demanded that U.S. prices be no higher than the lowest level paid in other developed countries.

One immediate effect is to help pharma in negotiations abroad: they can now credibly say, “We can’t sell to you at that discount, because you’ll export your price back into the U.S.” But two big issues follow.

First, this won’t lower U.S. prices on current drugs. Firms are already profit-maximizing in the U.S. If they manage to raise prices in France, they don’t then announce, “Great news—now we’ll charge less in America.” The potential upside of the Trump plan isn’t lower prices but higher pharma profits, which strengthens incentives to invest in R&D. If profits rise, we may get more drugs in the long run. But try telling the American voter that higher pharma profits are good.

The second issue is that the plan can backfire.

In our textbook, Modern Principles, Tyler and I discuss almost exactly this scenario: suppose policy effectively forces a single price across countries. Which price do firms choose—the low one abroad or the high one in the U.S.? Since a large share of profits comes from the U.S., they’re likely to choose the high price:

Pfizer CEO Albert Bourla was even more direct, saying it is time for countries such as France to pay more or go without new drugs. If forced to choose between reducing U.S. prices to France’s level or stopping supply to France, Pfizer would choose the latter, Bourla told reporters at a pharma-industry conference.

So the real question is: will other countries pay?

If France tried to force Americans to pay more to subsidize French price controls, U.S. voters would explode. Yet that’s essentially what other countries are being told but in reverse: “You must pay more so Americans can pay less.” Other countries are already stingier than the U.S., and they already bear costs for it—new drugs arrive more slowly abroad than here. Some governments may decide—foolishly, but understandably—that paying U.S.-level prices is politically impossible. If so, they won’t “harmonize upward.” They’ll follow the European way: ration, delay and go without.

In that case, nobody wins. Pharma profits fall, R&D declines, U.S. prices don’t magically drop, and patients abroad get fewer new drugs and worse care. Lose-lose-lose.

We don’t know the equilibrium, but lose-lose-lose is entirely plausible. Switzerland, for example, does not seem willing to pay more:

Yet Switzerland has shown little political willingness to pay more—threatening both the availability of medications in the country and its role as a global leader in developing therapies. Drug prices are the primary driver of the increasing cost of mandatory health coverage, and the topic generates heated debate during the annual reappraisal of insurance rates. “The Swiss cannot and must not pay for price reductions in the USA with their health insurance premiums,” says Elisabeth Baume-Schneider, Switzerland’s home affairs minister.

If many countries respond like Switzerland—and Trump’s unpopularity abroad doesn’t help—the sector ends up less profitable and innovation slows. Voters may feel less “ripped off,” but they’ll be buying that feeling with fewer drugs and sicker bodies.