Here is an impossible triangle for the west. We can finance two simultaneous proxy wars. Janet Yellen, the US treasury secretary, was right about this. We can also impose financial sanctions on other countries to force our will on them. And finally, we also have the ability to set standards for the rest of the world. But we cannot do all three at the same time. I would argue that we cannot even do two of them.

Dominique de Villepin, the former French prime minister, is right when he said that Hamas has laid a trap for the west, “one of maximum horror, of maximum cruelty,” as he said in a recent French TV interview. It is a trap that could lead to escalation, but also he said, to an end of western leadership, something we have taken for granted for generations.

I already thought that Vladimir Putin inadvertently laid a similar trap by triggering the west to impose maximal economic sanctions after his invasion of Ukraine last year. We are also imposing sanctions on China - Huawei, semiconductors, and soon electric cars. The sanctions have brought Russia and China closer together, and left many non-aligned countries like Brazil and India wary of following the western lead. The sanctions also drove EU countries that were dependent on Russian gas into recession.

Chinese news media and European conspiracy theorists portray western leaders as evil plotters who are out to impose their will on others. I actually think the opposite is the case. The West is acting out of a sense of moral superiority. It is the missionary zeal of the crusader that leads to actions that are deeply immoral. When the US administration and Congress impose secondary financial seconds on countries to make them comply with US policy, they end up defying the democratic rights of those countries and create resentment. There is a nastiness about the enforcement of one's own moral standards.

The EU is starting to do the same by enforcing its values into trade agreements. The planned EU trade deal with Latin America is going nowhere because the EU wants them to apply European standards to protect their own rainforests. Australia has just pulled out of trade talks with the EU because it just was not worth it for them to subject themselves to European finger-wagging.

Western support for Ukraine, too, is a morality tale. As the German war philosopher Carl von Clausewitz reminded us: never enter a war - or a proxy war for that matter - without a strategy to maintain political support throughout. And never enter without an exit strategy. What has been the exit strategy in Ukraine? Other than the unrealistic idea of total victory? What is the exit strategy in the Middle East?

De Villepin's great claim to fame was his intervention at the UN Security Council, when he, then in his role as French foreign minister, urged the US not to invade Iraq because the available evidence did not support it. Back then the US administration and its allies chose to breach international law when they invaded Iraq based on fake evidence. When we complain about Russia's breaches of international law, the rest of the world, the global south included, sees us as hypocrites.

For the EU, especially, the two proxy wars are a disaster on so many levels. Putin's aggression initially united the EU, but this unity is frail. Viktor Orbán and Robert Fico, the prime ministers of Hungary and Slovakia, are now starting to extract a price for their support for Ukraine aid. The Israel-Hamas war has divided Europeans right from the start. These divisions run within political parties, especially the left, and across countries.

What I worry about the most is the long-run effect of the cumulative impact of the political decisions we have taken since the start of the lock-down. After the fall of communism in 1989 and 1990, the west adjusted its economic model to globalisation. Technical innovations in global supply chains combined with liberalisation of trade and investment created a new global economic model. China's breath-taking economic development was dependent on savings surpluses that were absorbed by the west. Europe was one of the main beneficiaries. No European country ended up with more global inter-connections than Germany.

The geopolitical fragmentation that is occurring right now will have huge economic consequences for the west in the long-run. Did we think this through when we follow the US into this new world of geopolitical fragmentation?

After Russia invaded Ukraine, the first decision taken by the west was to freeze Russian assets. The dominant role of the dollar, and to a lesser extent the euro, allowed us to do this. But that came at a cost. The sanctions accelerated efforts by other countries to build payment systems, and strike trade deals amongst each other, which deliberately circumvented the western financial infrastructure. Financial sanctions are potent, in the same way as a nuclear bomb is potent: there is no foreseeable scenario in which you can use it and enjoy your victory afterwards. The irony is that the sanctions were not even very effective: Russia's economic growth this year exceeded that of most of the advanced western economies. The sanctions also failed to do the job of preventing Putin from waging war. A politically and financially exhausted West is now in grave danger of having to settle for an outcome in Ukraine many will perceive as a massive disappointment.

There is a case in favour western military support for Ukraine on the grounds that a Russian annexation would be a disaster for European security. But the cheerleading, the moral outrage, and the whatever-it-takes approach to foreign policy, are unbearable. Worse, they are self-defeating.

This column first appeared in the New Statesman