Trump’s arrest on charges of falsifying company records to conceal a hush money payout to a porn star has only boosted his standing in the polls. In the week or so after his arrest,his support among Republican voters leapt by around 20 percentage points.

And why shouldn’t it? Trump might be an affront to democracy,but the effort to pursue him over this case is another. The prosecutor is an elected politician from the opposing political party,the Democrats. This is not an aberration. It is a serious flaw in the US justice system. The Trump case merely highlights it.

Americans think this situation is normal because they are inured to it. But how can the prosecution possibly be fair and dispassionate when it’s run by a politician pursuing a career in politics? In Australia,as in other Westminster democracies,prosecutors are employed by an independent office of state and serve as impartial public servants.

In New York County,where the Trump case is taking place,you have to run for election to become the chief prosecutor,called a district attorney. You have to raise funds,campaign for votes,make political promises and,inevitably,be a Democrat. Every New York County district attorney since 1942 has belonged to that party.

The incumbent isAlvin Bragg,who campaigned for the post while talking publicly about his investigations into Trump. Even if Bragg is operating strictly according to objective rules in prosecuting Trump,many Americans will never believe it.

This is not to argue that a politician should escape prosecution for crimes;it is to observe that a politically partisan justice system will never be accepted universally as a fair one. The huge sympathy vote that we’ve so far seen for Trump is the inevitable result.

And,as America’s democracy continues to teeter,a competing model is standing in the international marketplace to offer countries an alternative. China’s President Xi Jinping says that “the China model for a better social governance system offers a new option for other countries and nations” if they “want to speed up their development while preserving their independence”.

The Chinese Communist Party is waging a systemic challenge to the Western-dominated global system. And it is inviting other nations to join it. As the NATO alliance put it last year,Beijing’s “stated ambitions and coercive policies,” it asserted,“challenge our interests,security and values”.

As Australia learnt in the last three years,Beijing readily uses sticks in its attempts to dominate other nations,unsuccessfully in Australia’s case. But it also offers very appealing carrots.

China’s Belt and Road initiative continues to offer countries around the world investment on a vast scale,with an estimated $US1 trillion already lent to 150 countries for major infrastructure under the project. This made China the world’s largest official creditor.

And as the Belt and Road scheme faded from the news somewhat,Beijing has been busy retooling it. It has made fresh loans totalling $US240 billion to bail out debtor nations floundering under the burden of repayments,according toBoston University research published last month. Lessons are being learnt;the scheme rolls on.

One of the researchers,Christoph Trebesch,says that in China’s financing behaviour “we see clear historical parallels to when the US started its rise as a global financial power,from the 1930s onwards and especially after World War II.”

Above and beyond Belt and Road,China continues to offer new initiatives to appeal to other countries,especially those sitting outside the Western bloc of rich nations. As well as offering countries cheap telecommunications and surveillance systems,Beijing last year unveiled its Global Security Initiative as an alternative to US-led security order. It’s now added a Global Civilisation Initiative to its menu for an alternative world order.

So,any faltering by the West does not leave a vacuum but an opening for Beijing and its allies. We have to hope that US democracy survives. Because when democratic states under pressure from autocratic regimes need help,they cannot turn to the Global Security Initiative. They turn to the US.

When Ukraine is invaded by Russia,when Finland and Sweden seek security from Moscow,or when Taiwan or Australia or Japan or the Philippines seek help against the encroachments of autocratic China,democracies depend on America. It won’t be pretty,but democracies have to hope that it survives its trial.

Cut through the noise of federal politics with news,views and expert analysis from Jacqueline Maley.Subscribers can sign up to our weekly Inside Politics newsletter here.