Speaker of the House Johnson is trying to rally support behind a novel way of funding Ukraine's war against Russia.

He suggested to Fox News on March 31 that he would try to rally his divided party behind the so-called REPO Act. That piece of legislation would allow President Biden, working with European allies, to seize Russian currency reserves frozen in the West and use them to aid Ukraine.
Grabbing these reserves would be politically convenient. Since Russia’s invasion of Ukraine in February 2022, the United States and its allies have thrown more than a quarter-trillion dollars into the war, to little ultimate effect. Ukraine has lately suffered a string of battlefield defeats.
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The REPO Act, by contrast, could make “Russia foot the bill for its own aggression,” as a group of Brookings Institution scholars puts it. Mr. Johnson himself calls it “pure poetry.” It is a tempting idea.

It's almost as if a Nigerian prince emailed congress and offered them millions of dollars if he only opened up his bank account.
The dollar is only the reserve currency in the world if everyone uses it. If we start stealing the currency reserves of foreign countries then in the end only our allies will use the dollar. Any nation that might find itself afoul of the interests of the United States could quickly find their own currency reserves being used to fund their demise. High on that list would be China, and their $1 Trillion in dollar assets. But it would be wrong to stop there. It would also be wrong to think that this stops at our borders.

At that time, Russia's central bank held around $207 billion in euro assets, $67 billion in U.S. dollar assets and $37 billion in British pound assets.
It also had holdings comprising $36 billion of Japanese yen, $19 billion in Canadian dollars, $6 billion in Australian dollars and $1.8 billion in Singapore dollars. Its Swiss franc holdings were about $1 billion.

Remember when the Trump administration set out to cause regime change in Venezuela? At the time Venezuela held nearly $2 billion in gold in London.

On Friday, the High Court of England and Wales decided in favor of opposition politician Juan Guaidó and dismissed a new effort by the Venezuelan Central Bank (BCV) to regain control over the reserves worth an estimated US $1.7 billion.

England refuses to return the gold to Venezuela despite the fact that former Venezuela opposition leader Juan Guaido is no longer recognised by Britain's government as the country's leader. What are the consequences of losing world reserve currency status?

We exercise a degree of control over the world economy because the world, for trading purposes, allows its transactions to pass through our currency. This leaves us with cheaper transaction costs and lighter financial burdens. It gives us leeway to run up debt ($34 trillion of it so far) that other countries lack.
If Russia, China and other diplomatic rivals were to decide that their dollar assets were vulnerable and that they could no longer trust the dollar as a means of exchange, we would feel the pain of that $34 trillion in debt in a way that we don’t now. Retaining the advantages of a reserve currency depends on our behaving as a trustworthy and neutral custodian of others’ assets. If we start stealing people’s money, that could change.