The act gives the president sweeping authority to remove non-citizens without court hearings if deemed a national threat

The act was introduced amid escalating tensions with France in the late 18th century.
US President Donald Trump on Saturday invoked the Alien Enemies Act – a wartime law last used in World War II – to deport individuals linked to Venezuela’s Tren de Aragua gang. This was the first use of the act since World War II.
Now a federal judge has blocked the deportations. Trump’s order designated the Venezuelan gang as an “invading force”, but US District Judge James E Boasberg, an Obama appointee, froze deportations for two weeks and set a Friday hearing to review legal challenges.