In 1987, the real estate developer Donald J. Trump wanted to buy an airplane. He sensed that the seller of the Boeing 727 was desperate, so he first offered a mere $5 million, “which was obviously ridiculously low,” he wrote in “Art of the Deal.” He boasts of buying the plane, worth $30 million new, for just $8 million.

This week, we saw the public policy equivalent of a $5 million offer for a $30 million plane.

The Trump administration demanded funding of its border wall as part of a deal to keep the government open, proposed a huge cut in taxes on businesses that would reduce government revenue by trillions, and leaked plans to abandon the North American Free Trade Agreement to try to force Canada and Mexico to agree to better conditions.

It is an approach that has defined Mr. Trump’s deal-making career: Make some seemingly outlandish offer as a starting point for negotiations to try to shift the entire frame of reference for the haggling that will follow. This strategy can certainly work in some circumstances. It also has distinct limits in complex negotiations like those in public policy, as the administration’s experience this week shows.

This strategy is also the opposite of the one often pursued by the last occupant of the Oval Office. President Obama tended to introduce policy proposals that were relatively close to where a negotiation with Congress might plausibly end up — often to the consternation of liberals, who felt he was negotiating against himself.