What Trump’s signature is worth if he loses Congress

In sixteen days the United States will renew the entire House of Representatives and slightly more than a third of the Senate. Almost everything written about these elections revolves around one question: whether Trump will be left without power. I think it is the wrong question. A president who loses Congress keeps the tariffs, the arms sales, the sanctions and command of the armed forces. What he loses is less visible and, for the rest of the world, rather more costly. He loses the ability to convince allies and adversaries that what he signs today will still stand when he is gone.

And with a president who cannot run again in 2028, that is almost everything.

Let us start with the numbers, because they do not say the same thing about the two chambers. Forecasting models consider it very likely that the Democrats will win back the House of Representatives. Call the Map put that probability at 82% yesterday, and other models raise it as high as 91%. The Senate is far more open. The same model gives the Democrats 56%, which in practice is little more than a coin toss with a bit of wind behind it. They need 51 seats, because in a 50-50 tie the deciding vote belongs to Vice President JD Vance.

Why is Trump in such poor shape two weeks before the vote? Last week’s AP-NORC poll explains it better than any model. Eight in ten voters disapprove of his handling of the cost of living, and three in four of his handling of the economy. The war with Iran and energy prices have done the rest. But the figure I find most revealing is a different one. Three quarters of Democrats say voting is “extremely important”, compared with six in ten Republicans. Midterm elections are decided by those who bother to turn out, and a fifteen-point gap in enthusiasm weighs more than any approval rating.

We have seen this film before. In 2018, during his first term, Trump lost the House. What came next serves as a guide. Weeks later the longest government shutdown in history began, 35 days, over funding for the wall with Mexico. Then came the subpoenas, the hearings and, in December 2019, the first impeachment. Trump was acquitted by a Republican Senate and carried on governing as he pleased in almost everything that depended on him.

With the House lost, the Senate, at 56%, is almost a coin toss.

If the House changes hands, the effect will begin on 3 January, when the new Congress convenes, and the sequence will be similar. The Democrats will control the committees and the calendar, and they will have an immediate tool: the subpoena. They will be able to demand documents on the war with Iran, on the suspension of sanctions on Russia, on tariffs and on arms sales approved through the emergency route. They will be able to vote for another impeachment if they wish. What they will not be able to do is remove anyone, because conviction requires two thirds of the Senate and those votes do not exist even in the best Democratic scenario.

It helps me to think about it the way anyone who has worked in a company would. A Democratic House is a board of directors that cannot fire the chief executive but can summon him every Tuesday to explain the accounts.

It does not take away his signature. It forces him to justify every one.

Where it really bites is money. Budget bills originate in the House and need both chambers and the president’s signature. With a Democratic House and a Republican Senate, every spending bill becomes a tug of war, and the risk of a shutdown returns several times a year. Trump keeps the veto, and overriding it requires two thirds in both chambers. So nobody imposes their agenda. They block each other.

Here lies the nuance that many analyses overlook. Much of the power Trump wields over the world rests on old laws that Congress delegated to the presidency decades ago, and a new majority does not repeal them simply by arriving.

In February the Supreme Court shut the door on his use of the emergency economic powers law (IEEPA) to impose across-the-board tariffs. It was a serious defeat, but it did not take away the rest. According to the latest Congressional Research Service report, as of 30 September tariffs remained in force on steel, aluminium, cars, semiconductors and certain pharmaceuticals under Sections 232 and 301, as well as a 50% tariff on certain Canadian products under Section 338, a provision of the Tariff Act of 1930 that almost nobody remembered. To remove any of them, a Democratic House would need to pass a law, get it through the Senate and persuade Trump to sign it. Or muster two thirds against his veto. It is not going to happen.

Losing Congress does not take away Trump’s tariffs, arms sales or sanctions, because they rest on laws that Congress delegated to the presidency decades ago.

Something similar happens with arms. The law requires major sales to be notified to Congress 30 days in advance, but allows that period to be skipped if the executive certifies an emergency. The Administration has done so this year with Israel, the United Arab Emirates, Jordan, Kuwait and Qatar. And Congress has never managed to stop a sale through a resolution of disapproval.

The most telling case is Russia. Congress passed, by an overwhelming bipartisan majority, a package of sanctions against Moscow. Trump put it on hold days before it came into force, citing the national interest and a diesel deal with Putin. There were protests from Republicans and Democrats alike. There was no legislative response. A law with presidential waivers is a law the president can shelve, and changing it requires another law that he can also veto.

If Trump keeps almost all his tools, why should a foreign government care who controls Congress? Because foreign governments do not negotiate with today’s president. They negotiate with what they believe will still be standing in 2029. Any agreement that depends solely on an executive order can vanish with the next occupant of the White House, and 3 November will offer the first serious clue as to who that might be.

Russia has reasons to close deals now, while Trump’s signature is still worth something.

For Europe and Canada the practical consequence is a very specific temptation: sign little and wait. Why make lasting concessions on agriculture, digital regulation or energy purchases in exchange for a tariff cut that can be reversed by decree? I believe Brussels and Ottawa will negotiate with one eye on the clock, and a Democratic House that puts figures on the cost of tariffs to American consumers will give them arguments for dragging out the timetable.

Taiwan is in a more delicate position. It has already seen deliveries delayed while Washington prioritised munitions for the operation against Iran. An opposition Congress would scrutinise those decisions more closely, but scrutinising is not delivering missiles. The sensible course for Taipei, and also for Tokyo and Seoul, is to build up stockpiles, diversify suppliers and avoid depending on the political calendar of a single capital.

The Gulf monarchies bet heavily on their personal relationship with Trump, and this year’s emergency sales are the fruit of that bet. A Democratic House would investigate those deals one by one. It could not cancel them from a committee, but it could turn every new approval into a slower and more uncomfortable process.

With adversaries the logic is the same, but the incentive works the other way round.

Confusion suits Moscow, and a Trump defeat could have an effect few expect. If the Kremlin believes that the window of a president willing to suspend sanctions closes in 2029, it has every reason to close deals now, while that signature is still worth something. I find it hard to believe Putin has not already done the maths. Kyiv, by contrast, would gain allies on the committees willing to ask out loud why a law passed by almost the entire Capitol was shelved.

China plays at a different speed. Beijing has spent years learning to wait Washington out, and the Supreme Court has already done part of the work for it by striking down the emergency tariffs. A president with Congress against him is a president whose trade truces are worth less, and in a negotiation that translates into one thing only. Conceding less.

Iran is the most serious case, because there is a war under way. The War Powers Resolution exists, but presidents have spent half a century arguing about when it is triggered, and Congress’s effective tool is still money. If Tehran reads a Democratic Congress as the prelude to a funding cut, it will be in less of a hurry to negotiate. I do not know whether that reading would be correct. I know it is the one I would make in its place.

And the markets? Strategists’ favourite statistic says that the US stock market tends to rise in the twelve months after a midterm election, and that Wall Street likes gridlock because a paralysed government does not pass laws that hurt it. A divided Congress will not pass new tax cuts through reconciliation, and less new deficit is good news for the long end of the curve, where the term premium reflects precisely the fear that the Treasury will keep issuing without restraint. But gridlock also comes at a price. It is worth remembering the summer of 2011, when a divided Congress took the debt ceiling to the brink and S&P stripped the United States of its top rating. A government shutdown is noise for the index. Three in a row start to be more than noise for bonds and for the dollar.

A Democratic House can investigate, block budgets and force government shutdowns, but it cannot remove the president without two thirds of the Senate.

Within the stock market, the effects would not be evenly spread either. US defence manufacturers heavily exposed to exports to the Gulf would face more political noise on every contract. European ones would keep benefiting from the one clear lesson every government on the continent has drawn from these years: it is unwise to depend on a single supplier.

The figure to watch on the night of 3 November is not the House, which almost everyone considers lost for the Republicans. It is the Senate. With the House, the Democrats get a torch. With the Senate they also get the key to appointments, ambassadors, judges and treaties, and that really does begin to change how government works from the inside. Not even with both will they be able to undo what Trump has done without his signature or without two thirds they do not have.

What they will do is change everyone else’s calculations. The vote on 3 November does not decide whether Trump can keep signing. It decides how long the world will believe his signature lasts.