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We’re only three days into the new year, but President Trump’s foreign-policy agenda — or the tweeted version of it, at least — has already opened up several new dilemmas for the United States abroad.

On Monday, Trump threatened to cut foreign aid to Pakistan, tweeting that the United States had “foolishly” given its once-close counterterrorism ally $33 billion in aid since the early 2000s — and gotten “nothing but lies” in return.

The comment sparked a quick and angry response from Islamabad. “Recent statements and articulation by the American leadership were completely incomprehensible,” Pakistani officials said in a Tuesday statement, adding that Trump “struck with great insensitivity at the trust between two nations built over generations.” On Twitter, the country's defense minister retorted that Americans “have given us nothing but invective & mistrust” in the post-9/11 era.

With thousands more U.S. troops headed to Afghanistan this year, it’s hardly the ideal time to raise tensions with Pakistan. Trump has little to gain from alienating a nominal ally and important power broker in the region.

But in 2018, it’s no easier to tell why Trump has chosen to risk his policies on Twitter than it was last year — only that he’s as willing as ever to do so. Trump’s 2017 tweets repeatedly offended close U.S. allies — drawing rebukes from Britain, Germany, Sweden and other nations — undercut his own national security officials and sometimes made it hard to determine just what his administration’s position was on critical issues. So far this year, that counterproductive streak has been out in force.

One day after his Pakistan comments, Trump tweeted about the growing protest movement in Iran — and fears that Iran’s government will crack down harshly on demonstrators. “The people of Iran are finally acting against the brutal and corrupt Iranian regime,” Trump wrote. “The U.S. is watching!”

Some observers worry that Trump’s accusations and support for the protesters could become the pretext for that crackdown, especially after Iran’s supreme leader, Ayatollah Ali Khamenei, accused foreign enemies on Tuesday of “meddling” in the country’s affairs. “In recent days, enemies of Iran used different tools including cash, weapons, politics and intelligence apparatus to create troubles for the Islamic Republic,” Khamenei said, without naming any countries. A different official later directly blamed the United States, as well as Britain and Saudi Arabia.

And while Iran’s establishment was apparently surprised by the intensity and durability of the protests, according to Erin Cunningham, there’s no sign yet of cracks among Iran’s security and clerical leadership. “This dynamic — unarmed, unorganized, leaderless citizens seeking economic dignity and pluralism, versus a heavily armed, organized, rapacious ruling theocracy that espouses martyrdom — is not a recipe for success,” Karim Sadjadpour, an analyst at the Carnegie Endowment for International Peace, wrote in the Atlantic.

Given the slim chance that the protests will result in major changes, Trump may have been well advised to heed the advice of Philip Gordon, an assistant secretary of state in the Obama administration, who urged the president last week to "[keep] quiet and do nothing” — much like his predecessor did during protests in 2009.

“It was never clear what difference American rhetorical support would have made then, other than allowing the Iranian government to depict the protesters as American lackeys, giving the security services more of a pretext to crack down violently,” Gordon wrote in the New York Times.

On Iran, however Trump’s most significant decision is yet to come, and it probably has nothing to do with protests. It remains hard to predict what would happen if Trump again imposes sanctions on Tehran, a move that could effectively reverse the Iran nuclear deal. While supporters of such a scenario hope that sanctions would destabilize Iran’s leadership, it could also make efforts to blame the United States for Iran’s economic woes all the easier — and isolate Washington if European countries carry on with the accord.

But the president already appears convinced that sanctions and “ ‘other’ pressures are beginning to have a big impact” elsewhere, as he wrote Tuesday, the day after North Korean dictator Kim Jong Un made new threats against the United States but also offered to send a delegation to South Korea for direct talks before the opening of the Winter Olympics there next month.

Trump appeared eager to take credit for Kim’s offer, and North Korea’s sudden willingness to talk may indeed be due to Trump’s hostile rhetoric toward Pyongyang — but for reasons he probably won’t appreciate. He and South Korean President Moon Jae-in have publicly sparred in recent months, with Trump accusing his ally of “appeasement” in dealing with North Korea. Some analysts believe Kim may be seeking to exploit the simmering tensions between Washington and Seoul.

“Kim sees a rare chance here to take the side of the South Koreans, against President Trump,” Robert Litwak, a North Korea-focused researcher with the Woodrow Wilson International Center for Scholars, said to the New York Times.

Of course, none of these reactions should come as a surprise to Trump — or anyone else: 2017 was filled with examples of the often-unintended effects of Trump’s social media diplomacy. As my colleague Erin Cunningham reported in November, for example, the escalating tensions between Iran and the United States provided hard-liners with an opportunity to more fiercely target their critics.

But the early days of 2018 suggest that Trump and his team have no intention of learning any lessons from the last 12 months. On Tuesday night, Trump added yet another tweet addressed to North Korea that seemed, in the eyes of some observers, to threaten nuclear war. If nothing else, it reminded us all that there's probably another tumultuous year ahead.

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