On Friday, US President Donald Trump signed an executive order placing new restrictions on immigrants from certain countries entering the US.

Immigrants from seven mainly Muslim countries - Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen - will not be allowed into the US for 90 days, with some exemptions for diplomats.

The order also indefinitely cancels the US' programme on Syrian refugees, as well as placing wider restrictions on the US refugee programme (no more than 50,000 refugees will be admitted this year).

"In order to protect Americans, the United States must ensure that those admitted to this country do not bear hostile attitudes toward it and its founding principles," the order notes.

The new rules led to chaotic scenes in US airports, a number of hasty legal actions, international condemnation and large protests across several cities in the States. 

Critics have referred to the order as effectively a 'Muslim ban' targeted at the seven countries - although the White House has denied these accusations.

The seven countries

The current ban is an undeniable escalation of already strict US immigration policy - policies which were already heavily tightened in the years after 9/11. 

However, one interesting thing to note about the order - which has been published in full in US media - is that it only mentions Syria by name. For the wider ban, it instead refers to "aliens from countries referred to in section 217(a)(12) of the [Immigration and Nationality Act], 8 U.S.C. 1187(a)(12)".

In this photo taken on April 4, 2015, a street is filled with debris and abandoned houses in the city of Benghazi, Libya. Picture by Mohamed Salama AP/Press Association Images

As CNN notes, in December 2015 Barack Obama signed into law limited restrictions on certain travelers who had visited Iran, Iraq, Sudan, or Syria.

In February of last year, the Department of Homeland Security (DHS) announced it added Libya, Somalia, and Yemen - "three countries of concern" - to that list. Hence, you have the seven countries now hit with the travel ban.

Those earlier actions limited the Visa Waiver Program travel for "certain individuals" who had traveled to the countries since March 1st, 2011. The actions were taken to combat what was described as the "growing threat from foreign terrorist fighters".

The DHS noted: "The Secretary of Homeland Security may waive these restrictions if he determines that such a waiver is in the law enforcement or national security interests of the United States". It cited journalists, NGO workers, government officials and others who were likely to have any restrictions waived.

Several media outlets reported over the weekend that the newly-issued order excluded countries - such as Saudi Arabia - where Donald Trump has business interests.

Although such 'conflict of interest' allegations deserve scrutiny, it is true that the countries chosen do adhere to previous US policy regarding the region. Several of the countries - including Iraq, Yemen and Somalia - have been targeted by US military action or drone strikes.

While the Trump administration is correct in the suggestion that these are "the same countries previously identified by the Obama administration", other claims made by the current administration are on shakier ground.

Trump has suggested: "My policy is similar to what President Obama did in 2011 when he banned visas for refugees from Iraq for six months."

As The Washington Post notes, there are significant differences between Trump's actions and Obama's six years ago.

The paper explains: "Obama responded to an actual threat [...] Under congressional pressure, officials decided to reexamine all previous refugees and also impose new screening procedures, which led to a slowdown in processing new applications.

"Trump, by contrast, issued his executive order without any known triggering threat."

"Muslim ban"

Defending the move, President Trump said: "To be clear, this is not a Muslim ban, as the media is falsely reporting. This is not about religion - this is about terror and keeping our country safe."

However, concerns that this and indeed future actions could be targeting Muslims specifically have their origins in claims made by Donald Trump himself during his whirlwind political rise.

Picture by Paul Vernon AP/Press Association Images

As a statement in December 2015, the Trump campaign clearly stated: "Donald J Trump is calling for a total and complete shutdown of Muslims entering the United States until our country's representatives can figure out what is going on." The suggestion was downplayed later in the campaign.

The initial suggestion was widely denounced, including by Mr Trump's future running mate Mike Pence in a Tweet that has gone viral in recent days.

Calls to ban Muslims from entering the U.S. are offensive and unconstitutional.

— Governor Mike Pence (@GovPenceIN) December 8, 2015

In an interview over the weekend, former New York mayor and Trump confidante Rudy Giuliani said: "When [Trump] first announced it, he said 'Muslim ban.' He called me up. He said, 'Put a commission together. Show me the right way to do it legally.'"

Trump's Chief of Staff Reince Priebus yesterday refused to rule out an extension of such a ban in the future. In an interview on NBC yesterday, he said: "Perhaps other countries needed to be added to an executive order going forward."

It should also be pointed out that the order makes explicit reference to religion, stating officials can "prioritize refugee claims made by individuals on the basis of religious-based persecution, provided that the religion of the individual is a minority religion in the individual’s country of nationality".

Strengthening borders

Demonstrators gather outside Tom Bradley International Terminal during a protest against President Donald Trump's travel ban. Picture by Ryan Kang AP/Press Association Images

Ultimately, the Trump team has repeatedly stressed their commitment to strengthening borders and combating terrorism - whether that's through strict immigration controls or his pledge to build a wall along the US-Mexico border.

"We will again be issuing visas to all countries once we are sure we have reviewed and implemented the most secure policies over the next 90 days," Trump has stressed. For his supporters, this executive order marks a major step towards his promised policies.

James Carafano, the man who led Donald Trump’s homeland security transition team, spoke to Newstalk Breakfast about Mr Trump's intentions.

He explained: "The reason why those countries were picked is not because they're Muslim countries - it has to to do with the facts of the ground.

"What we all think - not just the Americans, the Europeans as well - is [foreign fighters are] going to flow into these countries of conflict in the Middle East, like Yemen, Somalia and Libya. From there they could well - either through a refugee train or a visa thing - try to come through the West or United States and attack."

However, critics have warned this executive order may do more bad than good.

As Republican Senators John McCain and Lindsey Graham argued in a joint statement: "This executive order sends a signal, intended or not, that America does not want Muslims coming into our country. That is why we fear this executive order may do more to help terrorist recruitment than improve our security.”