After President Trump's provocative tweets on Sunday wherein he urged European countries to "take back" and prosecute some 800 ISIS foreign fighters as US forces withdraw from Syria, or else "we will be forced to release them," the message has been met with shock, confusion and indifference in Europe. Trump had warned the terrorists could subsequently "permeate Europe".

Possibly the most pathetic and somewhat ironic response came from Denmark, where a spokesperson for Prime Minister Lars Lokke Rasmussen said Copenhagen won’t take back Danish Islamic State foreign fighters to stand trial in the country, according to the German Press Agency DPA. “We are talking about the most dangerous people in the world. We should not take them back,” the spokesperson stressed, and added that the war in Syria is ongoing, making the US president's statement premature.

Image source: Alamy News/BBC

Germany's response was also interesting, given a government official framed ISIS fighters' ability to return as a "right". A spokeswoman for Germany’s interior ministry said, “In principle, all German citizens and those suspected of having fought for so-called Islamic State have the right to return.” She even added that German ISIS fighters have "consular access" — as if the terrorists would walk right up to some embassy window in Turkey or Beirut!

Noting that the Iraqi government has also of late contacted Germany to transport foreign fighters to their home country for trial, she added, “But in Syria, the German government cannot guarantee legal and consular duties for jailed German citizens due to the armed conflict there.”

The United States is asking Britain, France, Germany and other European allies to take back over 800 ISIS fighters that we captured in Syria and put them on trial. The Caliphate is ready to fall. The alternative is not a good one in that we will be forced to release them........ — Donald J. Trump (@realDonaldTrump) February 17, 2019

France, for its part, has already agreed to repatriate over 130 French Islamic State members as part of a deal reached in January with US-backed Syrian Democratic Forces (SDF) who are holding them, after which they will go through the French legal system. However, French Secretary of State Laurent Nuñez still insisted that the west's Kurdish allies would never merely let ISIS terrorists walk out their battlefield prisons free.

"It's the Kurds who hold them and we have every confidence in their ability to keep them," Nuñez told French broadcaster BFMTV on Sunday. "Anyway, if these individuals return to the national territory, they all have ongoing judicial proceedings, they will all be put on trial, and incarcerated," he said, in comments which appeared to leave it up to others to make happen.

....The U.S. does not want to watch as these ISIS fighters permeate Europe, which is where they are expected to go. We do so much, and spend so much - Time for others to step up and do the job that they are so capable of doing. We are pulling back after 100% Caliphate victory! — Donald J. Trump (@realDonaldTrump) February 17, 2019

And representing the Belgian government, Justice Minister Koen Geens charged Trump with blindsiding his European allies with the demand, which included Trump underscoring that it is "time for others to step up and do the job" before it's too late. "It would have been nice for friendly nations to have these kinds of questions raised through the usual diplomatic channels rather than a tweet in the middle of the night," Geens said during a broadcast interview on Sunday, according to the AFP.

Meanwhile in the UK the issue has recently become politically explosive as debate over so-called British jihadist bride Shamima Begum continues. The now 19-year old joined Islamic State in 2015 after fleeing the UK when she was just 15. She's now given birth in a Syrian refugee camp and is demanding safe return to Britain for fear that she and her child could die in the camp, so near the war zone.

Conservatives in Britain, such as Interior Minister Sajid Javid have argued that "dangerous individuals" coming back to the UK from battlefields in the Middle East should be stripped of their British citizenship. He said this option has already been "so far exercises more than 100 times," otherwise he also advocates prosecution of apprehended returning suspects "regardless of their age and gender."

Identified as French nationals fighting within ISIS' ranks, via Khaama press news agency

The UN has estimated that in total up to 42,000 foreign fighters traveled to Iraq and Syria to join IS — which appears a very conservative estimate — and which includes about 900 from Germany and 850 from Britain.

SDF leaders have previously complained about the "lack the capacity" for mass incarceration of ISIS terrorists and the inability to have proper battlefield trials for them. Recent estimates have put the number of ISIS militants in US-SDF battlefield jails at over 1000, though Trump put the number at 800 in his tweet.

However, even once they do return to Europe it's unclear the extent to which they'll be properly prosecuted and locked in prison by European authorities.

For example, another fresh controversy that lately erupted in Britain involved a 29-year old UK woman who traveled to join ISIS, and was convicted for membership in a terrorist group upon her return to Britain. She was jailed on a six year sentence in 2016, but is now already walking free a mere less than three years after her conviction.