In the waning days of the Biden administration, President-elect Trump is bucking his predecessor's "don't" doctrine as a deterrent to foreign adversaries, instead issuing tough warnings before even taking office. 

"If the hostages are not released prior to January 20, 2025, the date that I proudly assume Office as President of the United States, there will be ALL HELL TO PAY in the Middle East, and for those in charge who perpetrated these atrocities against Humanity," Trump warned Hamas on his Truth Social account Monday. 

"Everybody is talking about the hostages who are being held so violently, inhumanely, and against the will of the entire World, in the Middle East – But it’s all talk, and no action!" Trump added. 

War broke out in the Middle East on Oct. 7, 2023, when Hamas launched a surprise attack on Israel. Terrorists killed more than 1,100 people and kidnapped more than 200, with Hamas still holding 101 hostages, including seven Americans, in Gaza more than a year after the war began. 

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The White House and Israeli government have worked for months to secure a hostage release deal, but have been unsuccessful. 

Trump's tough language against Hamas, which included warning those responsible for holding the hostages that they "will be hit harder than anybody has been hit in the long and storied History of the United States of America," stands in stark contrast to President Biden's "don't" doctrine regarding the war in Israel. 

After the war began last year, Biden delivered remarks from Israel where he warned adversaries of Israel and the U.S. "don't" attack Israel. 

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"And my message to any state or any other hostile actor thinking about attacking Israel remains the same as it was a week ago: Don’t. Don’t. Don’t," he said. 

War continued despite the warning, including from Iranian proxies against Israel. 

This year, Biden doubled down on his warning of "don't" aimed at Iran. When asked by reporters about Iran's expectation to attack Israel in April, he said his message to Tehran is: "Don't." 

"We are devoted to the defense of Israel. We will support Israel. We will help defend Israel and Iran will not succeed," he added. 

Again in August, Biden warned Iran against attacking Israel with the one-word threat.  

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Biden's common response to deter foreign adversaries from attacking Israel is viewed as a failed policy, with conservative security experts and others slamming the message as weak. 

"The Administration keeps saying 'don't' to Iran – but then does nothing to impose costs. This weakness means the risk from Iran continues to grow," former Secretary of State Mike Pompeo tweeted in August. 

"Well, he said, ‘Don’t’ multiple times, and ‘Don’t’ isn’t a national security policy," Pompeo added later in a comment to Fox News. "It’s not even a deterrent.

"So much for President Biden telling bad guys ‘Don’t’ actually being an effective deterrent. Every time he says 'Don’t,' they do," Sen. Lindsey Graham, R-S.C., wrote in a post in April, after Iran launched more than 300 missiles and drones at Israel. 

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"Biden's approach with Iran and the Middle East is backwards," Rep. Nancy Mace, R-S.C., wrote on X. "Now as we risk entering WWIII, the US must stand by Israel's commitment to democracy. The president must stand firm, and stop coddling Iran immediately."

"I guess Biden's speechwriters have him down to one word now. At least he can remember it. Worse when referring to the hospital carnage he calls Hamas the other team," Fox News' Greg Gutfeld quipped after the war in Israel broke out last year, mocking Biden's use of the word "don't." 

Trump had campaigned on ending the wars in both Ukraine and Israel, both of which began under the Biden administration, and claimed that neither war would have been launched if he had been president. 

"The Ukraine situation is so horrible, the Israeli situation is so horrible. We are going to get them solved very fast," Trump said on the campaign trail in January. 

Israeli officials celebrated Trump's tough stance against terrorists in the Middle East and his demand for hostages to be released by next month. 

"Thank you and bless you Mr. President-elect," President Isaac Herzog of Israel said in a post on social media. "We all pray for the moment we see our sisters and brothers back home!"

The nation's finance minister, Bezalel Smotrich, added, "How refreshing it is to hear clear and morally sound statements that do not create a false equivalence or call for addressing ‘both sides.’ This is the way to bring back the hostages: by increasing the pressure and the costs for Hamas and its supporters, and defeating them, rather than giving in to their absurd demands."

Trump will be inaugurated as the nation's 47th president on Jan. 20, with his team celebrating that he's already following through on his campaign promises. 

"President Trump is working towards international peace. In anticipation of the incoming Trump administration, Iran has called off its reprisal attack on Israel and negotiations to end the war in Gaza and Russia's war in Ukraine have accelerated. One former NATO Supreme Allied Commander says America's enemies are 'concerned, they're nervous – [and] they ought to be,'" the Trump War Room said in an email this week titled "Promises Kept – And President Trump Hasn't Even Been Inaugurated Yet."