"President Trump acted in the best interest of the Constitution when he withdrew American troops from Syria," said Fox News judicial analyst Judge Andrew Napolitano on Fox Nation.

WHY IS TURKEY ATTACKING THE KURDS?

Earlier this month, Trump decided that 1,000 U.S. troops would be pulled out of northern Syria. The move provided an opportunity for Turkish forces to launch a military assault on the Syrian Kurds in the region, whom the Turkish government considers to the terrorists.

"While it may not be a popular move from both sides of the aisle, with many Republicans and Democrats referring to it as a moral betrayal. The president, legally speaking, was on very solid ground when he pulled back U.S. forces from Syria, of all places," explained Judge Nap on his show "Liberty Files with Judge Andrew Napolitano."

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"Why? Because Congress never authorized U.S. involvement in the Syrian civil war in the first place," he continued. "The war powers are clearly articulated in the plain language of the Constitution itself. Congress declares war. The president wages war. Sending American troops to Syria was never authorized by Congress and more so -- it's not even in the best national security interests of the United States."

President Trump has received bipartisan criticism of his decision to pull out the U.S. forces.  Sen. Lindsey Graham, R-S.C.. has expressed support for Kurdish fighters, who have fought alongside U.S. troops against the Islamic State terror group. He previously called Trump's move "shortsighted" and "irresponsible."

Trump announced on Wednesday that the U.S. is lifting sanctions that were imposed on Turkey after Turkish attacks on Kurdish forces. The NATO ally has now agreed to permanently stop fighting Kurdish forces in Syria.

Judge Napolitano said that Congress should act if they believe a U.S. military role in the region is necessary.

"If Congress wanted American troops in Syria, it could declare war on the government there," he said. "That would be immoral, unlawful and absurd. But it would at least make American troops' presence constitutional.

"If the government wishes to remain in the conflict, then the legislative branch must repeal power that it has given away.  The authorization for use of military force in 2001 and the authorization in 2002 and the War Powers Resolution, both of which have given past presidents and President Trump leeway to invoke interventions abroad, are profoundly unconstitutional and outdated and open-ended."

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Judge Nap concluded, by saying, "Congress can reclaim its constitutional power as the only entity in the federal government constitutionally authorized to declare war. Meanwhile, the president not only followed through with his controversial campaign promise but complied with his duty to uphold the Constitution. It is Congress that must take hold of the powers entrusted to it 200 years ago."

To hear more from Judge Andrew Napolitano as he explores government regulation and personal freedom, join Fox Nation and watch the latest episode of "Liberty Files with Judge Andrew Napolitano" today.

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The Associated Press contributed to this report.