President Donald Trump is a self-proclaimed expert on “the art of the deal.” But in the case of brokering peace in Ukraine, former Trump adviser Fiona Hill believes the president cares less about the future of sovereignty for Ukrainians, and more about his own personal gains.

“We’re starting to see a decoupling of Trump’s interest in improving and resetting the U.S.-Russia relationship from what’s going on in Ukraine,” she told GBH’s Boston Public Radio Monday. “He wants to have a big sit-down with [Russian President Vladimir] Putin to talk about all the things he has on his agenda, of course that means business deals, and all the kinds of personal enrichment he’s always got in mind.”

Hill, who worked on Russian affairs on the National Security Council during Trump’s first term, has been warning of Russian expansion for years. In 2019, Hill testified at Trump’s first impeachment inquiry that Russia actively interfered in the 2016 election that first sent him to the White House.

She warns now that Trump’s affinity for strong men and authoritarian leadership is a vulnerability, especially when dealing with the former-KGB-officer-turned-Russian-president.

“Putin’s got on Trump what we all have on Trump: We know he’s an incredibly flawed individual and can be manipulated,” she said.

In terms of any ceasefire deal brokered under Trump’s leadership, Hill believes the Ukrainians will need to make concessions.

“The message really is that you cannot rely on the United States. [Ukraine] is going to have to do damage limitation, to figure out a way to save something over time by working with their neighbors who also have a vested interest in European security,” Hill said.

She says that, though tough times could be coming for European countries with the new tariffs, it’ll be essential for Ukraine to bolster its European relationships and aid; others will need to step up where the United States has decided to step back.

It’s a message she said extends to threats on democracy at home, too. Hill said people must come together through collective action to defend democratic institutions under attack.

“It’s kind of like the issue everybody’s facing at the moment; you’ve got to diversify your vulnerability,” she said. “No institution is going to be safe from predation by the government. ... You can’t just stand alone because you’ll get picked off. You’ve got to push back, and you’ve got to do it collectively.”