Donald Trump’s presidency will have geopolitical consequences. Most of the world wants to know what he will do. But that depends on what he can do—which you may remember us discussing before. That, in turn, will be determined by US political dynamics and counteractions of other nations.

This is a case where politics rises to the level of geopolitics. Trump’s actions will be conditioned by the actions of other players, particularly in Congress. Trump, after all, will only be the president.

His powers will be limited. For most of the things he wants to do, he needs Congress to go along. Therefore, the American stance toward the world will depend more on what Congress decides to do.

What Congressmen and Senators Want Most

It is to be re-elected. To be re-elected, they need voters’ support. Congressmen are all peering in the future.

Now, they’re trying to guess whether by then Trump will have developed support that they can use to win. They’re wondering if he will stay where he is now, or whether his support will deteriorate further.

If they follow Trump and his support declines, re-election will be difficult in many districts. If Trump increases his popularity, supporting him will be a stroke of genius.

This may be regarded as cynicism or as faithfully representing your constituency. But that is what they are thinking.

And this is what foreign governments are considering as well. They are asking themselves whether Trump will be strong enough in Congress to carry out all his initiatives.

Or whether he will be paralyzed by a hostile Congress and poor political ratings. China, Mexico, and Russia know the election was not the end of the struggle, but the beginning.

Trump will need to increase his positive ratings a lot to demonstrate to Congress that he is trending upward.

Juggling Campaign Promises with Senators’ Needs

If Trump doesn’t pull this off, congressmen will have to carefully evaluate the mood in their districts. They will have to make the difficult decision of whether to oppose Trump. And if they do oppose him, on what issues.

Foreign governments will also be assessing their options. It is not simply being president that makes you powerful, it is the support you have in Congress. That depends on the support you have in the country. If he had blown away Clinton, he wouldn’t face this problem. Since he didn’t, he does.

And that makes Trump’s first 100 days far more important to him than to previous presidents. He needs to demonstrate to his party that he can craft and pass legislation that will raise his popularity.

He has to do this while making it clear to his supporters he won’t ignore campaign promises. This is hard to do.

Congressmen and senators who might lose the next election if they support the measures that are closest to the heart of Trump’s base will resist. And with only a 52-48 majority in the Senate, it will be tough.

It is always important to remember that in the American system, presidents have minimal power over senators and congressmen. Their greatest influence comes from popularity they can transfer to candidates from their party—at a price.

Watch George Friedman’s Ground-breaking Documentary, Crisis & Chaos: Are We Moving Toward World War III?

Russian adventurism. An ailing EU. Devastation in the Middle East. These are just three symptoms of a systemic instability engulfing a region that’s home to 5 billion of the planet’s 7 billion people.

In this provocative documentary from Mauldin Economics and Geopolitical Futures, George Friedman uncovers the crises convulsing Europe, the Middle East, and Asia… and reveals the geopolitical chess moves that could trigger global conflict. Register to watch the documentary now.