I don't think there is any evidence that they actually need the dollar swap line - the dirham-dollar peg isn't at any risk and they have plenty of money for fiscal flexibility going into the foreseeable future. If you take financial reasons off of the table then it is clear it is just a political play for a bigger seat at the table with the US.
The Saudis did it to Biden in 2023, the UAE sees the opportunity to do it to Trump now.
They need the dollars because they're an import-oriented economy, almost all of which are conducted in dollars (nobody wants their dirhams because oil is priced in dollars anyways). Dollars are also useful for their sovereign funds to invest into the US, either in the stock market, or in private equity.
What happened this week - they announced they might start selling in yuan, they left the OPEC, and they started a new wealth fund to invest exclusively in China. That gives them an alternative for the dollar-peg since China is their biggest import partner anyways, while also giving their surplus yuan an alternative channel of investment into China.
Still they need the dollar-swap for the essentials - food from India and Pakistan, neither of which will accept their dirhams unless they get exclusive deals (which are not allowed in OPEC). It helps for them that India and Pakistan need lots of oil, and that a dollar peg benefits the UAE more than it does either nation. If the EU plays a greater role in trade, particularly in defence and maritime manufacturing, they will stockpile euros too, to the detriment of the dollar.
Still, they also bought some prime DC acreage to expand their US diplomatic corps, and will likely keep the Washington connection, so long as AI is perceived as useful. Right now, that's the only major export benefit the US provides the Gulf countries. This is them just hedging their bets.
At last report (Feb 2026) the UAE had ~$250b in foreign currency reserves. They have plenty of non-AED currency.
The Yuan is the current bogeyman the Gulf States use when they want attention from the US (not that they’re not diversifying, just that it isn’t a structural shift in a meaningful way). The UAE is making this play right now to make sure they are part of the conversation in deciding how things with Iran end and making sure their influence is sustained after the current administration.
The wealth fund is a way to deploy whatever yuan they receive while gaining political favor with China as well.