As President Donald Trump spent this week bitterly defending his temporarily blocked de facto Muslim ban, his administration is reportedly preparing a big arms deal with Saudi Arabia.

Saudi Arabia was notably excluded from Trump's controversial immigration ban, which barred U.S. entry to nationals from seven Muslim-majority countries and refugees.

The countries named in the ban — Syria, Iraq, Iran, Libya, Somalia, Sudan and Yemen — have not produced terrorists responsible for attacks on American soil.

President Donald Trump Pool/Getty Images

"The government has pointed to no evidence that any alien from any of the countries named in the order has perpetrated a terrorist attack in the United States," the judges' ruling in the 9th Circuit court said Thursday.

Yet the majority of people killed in domestic terrorist attacks were killed by Saudis.

The seven targeted countries are mostly ravaged by poverty and, in some cases, civil war. Meanwhile, Saudi Arabia ranks among the 15 richest countries in the world.

Here's what's happened

The White House has been tightlipped about the alleged arms deal, but unnamed government officials involved directly in the reported deal told the Washington Times Tuesday that a major sale of arms to Saudi Arabia was imminent.

Saudi Arabia is reportedly set to buy a $300 million precision-guided missile technology package from the United States — a deal confirmed by anonymous Congressional sources.

"These are significant sales for key allies in the Gulf who are facing the threat from Iran and who can contribute to the fight against the Islamic State," one of the officials said to the Washington Times.

A Saudi child holds up a national flag with picture of King Abdullah bin Abdulaziz during celebrations marking the 83rd Saudi Arabian National Day in Riyadh. Fayez Nureldine/Getty Images

"Whereas the Obama administration held back on these, they're now in the new administration's court for a decision — and I would anticipate the decision will be to move forward," the official added.

According to the U.S. officials, who spoke on the condition of anonymity, a deal with Bahrain is in the works, too.

The U.S. has a long history of making billion dollar arms deals with Saudi Arabia, and America's key ally, the United Kingdom, continues to sell arms to the oil-rich Arab nation, a decision currently under judicial review.

British Prime Minister Theresa May meets King Salman bin Abdulaziz al Saud of Saudi Arabia on December 6, 2016 in Manama, Bahrain. Pool/Getty Images

Here's why it matters

Saudi terrorists have been responsible for the vast majority of people who have died in terrorist attacks committed on U.S. soil.

Between 1975 and 2015, there have been 40 successful terrorists on U.S. soil, according to the think tank Cato Institute. Nineteen of those were responsible for executing 9/11, 15 of whom were from Saudi Arabia.

With 2,983 deaths from 9/11, the 15 Saudi nationals killed an average of 2,355 people. However, the remaining 25 terrorists over the 40 year period were collectively responsible for a an average of 669 deaths.

WASHINGTON, DC - SEPTEMBER 04: U.S. President Barack Obama looks on as King Salman bin Abd alAziz of Saudi Arabia speaks during a bilateral meeting in the Oval Office of the White House September 4, 2015 in Washington, D.C. The President and the King were expected to discuss various issues including joint security and counter-terrorism efforts Pool/Getty Images

None of the other 25 people were from the nations barred in Trump's travel ban.

After orchestrating a number of arms deals with Saudi Arabia, the Obama administration blocked a sale of cluster bombs in May over concerns about Saudi Arabia's bombing in Yemen, the battleground for a lager proxy war against Iran.

The military coalition in Yemen, led by Saudi Arabia, "may amount to war crimes," according to United Nations sanctions monitors, Reuters reports.

A Yemeni boy sits amidst the rubble of damaged houses following reported Saudi-led coalition air strikes on the outskirts of the Yemeni capital Sanaa on February 1, 2017. Mohammed Huwais/Getty Images

And then there's Saudi Arabia's involvement in the Syrian civil war. Their missile attacks and military involvement against Syrian President Bashar al-Assad have made Saudi partly responsible for the carnage and displacement of millions of people in Syria.

Supporting and encouraging Saudi Arabia's military might has major implications for the world and regional stability — that means it unavoidably has implications for national security too.