Amid reports of anti-government protests in Iran over the weekend, President Trump issued a series of tweets aimed at pressuring Tehran, demanding that human rights groups be allowed in to “monitor and report” on the unrest.

“There can not be another massacre of peaceful protesters, nor an internet shutdown,” Trump wrote in both Farsi and English, his rare use of a foreign language making the challenge to Iran’s leadership more pointed. “The world is watching.”

Several hours later in Hong Kong, Kenneth Roth, the executive director of U.S.-based Human Rights Watch, was denied entry after landing at the airport. A Chinese government spokesman in Beijing said the ban was the nation’s “sovereign right” given such groups’ support of mass pro-democracy protests since last summer.

Trump was silent on Roth’s plight.

To much of the world, the protests in Hong Kong and Tehran have reflected similar frustrations of ordinary citizens over the control, repression and lack of accountability of authoritarian regimes. Reports of strong-arm tactics being used by authorities to suppress the uprisings in Tehran — which flared anew after the Iranian military admitted it had mistakenly shot down a Ukrainian passenger jet, killing all 176 on board, amid a military operation against the United States — echoed some of the bloodier confrontations in Hong Kong.

But the twin flash points prompted markedly different rhetorical responses from Trump, reflecting a president who has consistently used the promotion of human rights in a tactical and transactional manner, aimed primarily at winning concessions on security or trade, rather than as a broader expression of Western-style democratic values.

In the past few days, he has jumped all in to offer solidarity with the protesters in Iran. But he has been decidedly more circumspect on the situation in Hong Kong.

“Human rights principles are strong principles because they apply to everybody. When Trump picks and chooses where to promote human rights, he undermines the credibility of the U.S. government’s voice,” said Roth, who had intended to release a report critical of Beijing at a news conference in Hong Kong.

“I don’t want to belittle the importance of the U.S. government support for Iran’s protesters, but that would be much more effective if it was applied in a more principled way,” Roth added. “It’s so easy to respond to Trump by claiming that he’s instrumentalizing human rights — using human rights as simply another tool in a battle with the clerics.”

Trump’s stream of tweets and retweets in support of the Iranian protesters in recent days came as the administration redoubled its “maximum pressure” campaign on Tehran after the military confrontation that resulted in the U.S. drone killing of Iran’s most powerful military commander and Iran’s firing of a dozen ballistic missiles at Iraqi bases housing U.S. troops on the night the Ukrainian plane was shot down.

The president also appeared eager to use the protests in Iran’s capital to score political points against Democrats, as he sought to paint House Speaker Nancy Pelosi (Calif.) and Senate Minority Leader Charles E. Schumer (N.Y.) as supportive of the Iranian regime amid their criticism of his foreign policy — and their efforts to impeach him.

Democrats have accused Trump of recklessly pulling the United States out of the Iran nuclear deal negotiated by the Obama administration, and many couched their support for the protesters by emphasizing their displeasure with Trump’s policies and recent actions toward Iran.

“I support the right of the people of Iran to peacefully protest against their corrupt government. But this isn’t about us,” Sen. Elizabeth Warren (D-Mass.) tweeted. “We should support them, including by lifting the Muslim Ban — not try to engineer regime change or recklessly risk a war.”

On Sunday, Trump dropped in another tweet in Farsi — translating an earlier tweet warning Iranian leaders: “DO NOT KILL YOUR PROTESTERS” — amid an angry tweetstorm about impeachment as the Sunday political talk shows were underway. Trump’s Republican allies clipped a response from Pelosi on ABC’s “This Week” — in which she said “there are different reasons why people are in the streets” — to suggest she did not believe the protesters were denouncing the regime.

Trump retweeted several posts from Twitter users — including several accounts with vague origins — referencing the Iran protests and employing the hashtag #NancyPelosiFakeNews. Among them was a post featuring a doctored image of Schumer wearing a turban and Pelosi a hijab, with text accusing them of rushing “to the Ayatollah’s rescue” — a meme that drew condemnation from Muslim Americans.

“Why the actual hell is the president of the United States using the way I and millions of other Americans dress and the religious beliefs that We hold as a slur,” wrote Hend Amry, a well-known Twitter voice.

By comparison, Trump has been far more reserved on the Hong Kong protests over Beijing’s attempt to impose stricter legal controls despite the long-standing “one country, two systems” governing approach to the island.

Though Trump has struck occasional notes of support for the protesters — including at a speech at the U.N. General Assembly last fall — he has been careful not to directly criticize President Xi Jinping amid ongoing trade negotiations.

Trump has praised Xi’s leadership and suggested that a leader called more ruthless than any Chinese head since Mao Zedong meet with the protesters. Last fall, Trump tweeted congratulations to China on the 70th anniversary of Communist Party rule, a message posted hours after a protester in Hong Kong was shot by authorities.

He has left it to Vice President Pence and Secretary of State Mike Pompeo to offer more-direct critiques of Beijing’s human rights record.

Samuel Chu, the managing director of the Washington-based Hong Kong Democracy Council, said he has emphasized to partners in Hong Kong that, given Trump’s transactional nature, “it is our job to align, as closely as possible, the administration’s political interests with our interests. It’s not for us to trust that this administration is going to do the right thing.”

Given Trump’s interest in a trade deal with Beijing, Chu said, his group focused much of its lobbying efforts on Congress. That strategy paid off in November when lawmakers passed a measure with veto-proof majorities that requires the administration to impose sanctions on Chinese officials for rights abuses in Hong Kong.

Trump signed the bill into law, though he also emphasized his friendship with Xi. This week, Trump will participate in a signing ceremony for a “phase one” trade deal with China.

Andrea Prasow, the Washington director of Human Rights Watch, said Trump’s inconsistent approach to human rights and protesters has undermined the United States’ ability to build coordinated, international pressure on oppressive regimes.

Though Trump led a robust sanctions campaign against North Korea in his first year, he has played down human rights issues since engaging in nuclear negotiations directly with dictator Kim Jong Un. And he has voiced almost no concerns about human rights abuses by Saudi Arabia as he builds a close relationship with its leaders.

“Trump is seen as so unpredictable and so transactional that it does not help build what Iran could really benefit from: international consensus,” Prasow said. “The initial reaction is that, ‘Hey, he’s talking about human rights!’ But it’s counterproductive when it’s coming from this administration, knowing that it will only be instrumentalized — and that it can turn on a dime.”