President Trump wants to push through the construction of a wall along the border with Mexico to declare a so-called national emergency.

a presidentorder and gives the president an opportunity to circumvent the separation of powers in the american system in a crisis.

Congress has so far not wanted to grant Trump the $ 5.7 billion he requested for the wall. With decision on state of emergency, he can get it off of military money and order the army to build it.

Since the ability was introduced in 1976 has various american presidents decided on the national emergency in 58 cases, and 31 of them are still active.

Almost all is about the international sanctions against governments, terrorists and criminals. In few cases have they been applied to specific crises, such as the swine flu epidemic of 2009 and the terrorist attacks of september 11, 2001.

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Donald Trump himself has already decided on three. One of them is about to impose sanctions ”in the event of foreign interference in an election in the united states”.

this time want to Trump use of the possibility in a way not done before. This will be the first time a state of emergency aims to accomplish a construction project.

to stop the emergency. It can stick through a resolution to that effect.

Read more: Trump to approve the budget – but announces at the same time of national emergency

If the democratic majority in the house of representatives to say yes to such a resolution, the senate republican majority to take a position to the within a certain period of time.

It will be politically tricky. Even many republican senators dislike Trumps the idea of a state of emergency to build a wall, but you go against the president, you risk to annoy his ushered a major period.

to complicate matters further, the president may veto a resolution, which congress in turn can tear it up with a two-thirds majority.

Senate majority leader Mitch McConnell has hinted to the president that there is a risk that he would lose such a vetostrid.

in addition in all probability to be admissible in court.

Trump’s motive is to increased illegal immigration over the border threatens U.S. security and constitute a humanitarian crisis.

Read more: Fierce criticism of the Trumps national emergency

But is illegal immigration a national crisis in the same way as an epidemic or a terrorist attack? And the battles Trumps action even against the constitution? There are legal questions a court must answer.

for Trumps drastic solution weak. Around 60 per cent is received in several measurements.

Also in this issue is the usual difference between democratic and republican voters, but even among republicans is between 20 and 26 per cent negative to the president of the republic will take to the national emergency.