Why China Keeps Exporting More Despite the Highest Tariffs in a Century

China's customs office reported that dollar-denominated exports rose 25% in August from a year earlier, to just over $400bn, leaving a monthly trade surplus of about $119bn. Over the first eight months of the year the surplus runs to roughly $806bn — on track to exceed $1trn for the third year running, after a record $1.19trn in 2025.

The detail that should stop an investor is not the size of the number but the circumstances. This boom is happening amid the harshest trade confrontation of modern times: the United States has doubled its tariffs on Chinese goods, and Europe has slapped sectoral duties on electric cars and steel. Export strength of this kind inside a tariff war looks like an anomaly, and a flattering one at that. It is not. It is the output of a deliberate machine, and the machine repays inspection more than any single month's figure.

The conventional story — tariffs tax Chinese goods at the border and thereby price them out of Western markets — misdescribes how the machine works. Border tariffs do raise the price of Chinese goods. They do not reach the incentives that produce so many of them. Three forces keep the tap open.

The keystone is a deliberately cheap yuan. The IMF estimates China's currency is undervalued by roughly a fifth, and by a third or more once surging gold imports are counted. Beijing keeps it there on purpose: state banks have been buying about $50bn a month to stop the yuan rising to where a trade surplus of this size would naturally push it. The currency is in effect a continuous, universal export subsidy. Raise a tariff over the wall and the currency subsidy simply lowers the selling price again. The two compete, and so far the currency has kept the upper hand.

Below it sits subsidised overcapacity. Beijing funnels cheap credit into manufacturing — electric vehicles, batteries, solar cells, now semiconductors — far beyond what Chinese households want. An industrial sector built to such a scale must sell abroad or choke on its own unsold output; China already ships more than ten million vehicles a year and, on some forecasts, could double that within three years. And because domestic demand is weak — GDP grew just 4.3% in the second quarter, with retail sales subdued — exports have become the only reliable growth valve. Net exports have contributed roughly six percentage points to China's growth over the past six years.

Two features of the data show the machine at work, and both deserve scepticism. Growth is increasingly a matter of volume sold at falling prices; the IMF has noted that export values rose while per-unit prices declined. And the surplus is being redirected rather than reduced. China's surplus with Europe and with Southeast Asia has widened, while its reported surplus with America barely moved despite the tariff hikes — because shipments increasingly travel through intermediaries. American import statistics therefore understate how much of the machine's output still ends up in American shops.

There is a genuine question of how durable the boom is, and it is worth stating plainly. Some of the surge is not conquest but borrowing from the future. The pattern of pulling shipments forward ahead of new tariff walls was studied by the IMF during the 2024-25 trade fight, and in 2026 trans-Pacific freight rates have climbed sharply, the signature of cargo rushed to beat the next round of duties. A cushion of front-loaded demand can deflate as quickly as it inflated; the arithmetic that flatters one quarter can hollow out the next.

For an American retail investor the export machine has three practical consequences, none of them a reason to chase the headlines.

First, treat the machine as a deflationary force on goods rather than a growth story. Cheap, subsidised Chinese output is why solar panels, batteries and electric vehicles keep getting cheaper. That is a gift to consumers and a recurring tax on the earnings of Western manufacturers that compete with them. Expect persistent margin pressure in autos, solar and materials, tariffs or no.

Second, resist buying the Chinese winners. The volumes are not translating into profits. BYD's overseas deliveries rose 70% in the first half of 2026 and its shares still fell, because price wars at home and a crowded field crush margins even for the leaders. In this model growth is manufactured at the expense of profitability; there is no clean home for a retail portfolio in the middle of it.

Third, watch the currency. The whole structure rests on yuan kept artificially cheap. It is the one lever that, if removed, would slow the machine faster than any tariff, which is why trade partners have begun pressing Beijing to let it appreciate. Read the yuan, and you read the future of the surplus.

The August figure is not really about August. It is a reminder that a country with weak domestic demand, a heavily subsidised industrial base and a deliberately undervalued currency will keep exporting its problems abroad, no matter how high the walls are raised. For investors that is a standing condition, not a passing number: a reason to expect cheap imports and squeezed Western margins, and to be sceptical of any single month's trade data, in either China's favour or against it. The honest test lies in whether the boom proves to be durable conquest or a front-loaded payback, and in whether the currency subsidy can survive a world that is increasingly uniting against it.