ANALYSIS: Trump Lands Back Where He Started on Immigration

Even by Trumpian standards, Wednesday's events capped a dizzying policy journey.

He meandered through all that territory and to both sides of the U.S.-Mexico border to land back where he started on a signature issue. His anger-tinged speech Wednesday night in Phoenix carried high expectations of a new tone and fresh policies but brought little of either.

"Anyone who has entered the United States illegally is subject to deportation," he declared. "Otherwise, we don't have a country."

Even by Trumpian standards, Wednesday's events capped a dizzying policy journey. The day's frenzy started with a surprise visit with the president of Mexico, where Trump was courteous and even complimentary toward his hosts.

He seemed like a downright conventional politician as he talked of a "constructive conversation" and "shared goals." Gone, for a few hours, was the Mexico he has portrayed over the past year and a half as a menacing enemy — siphoning American jobs and wages, taking advantage of free-trade agreements and sending rapists and drugs across a porous border.

Within hours, it became clear from both sides that the wall did come up in their private chat — raised by Pena Nieto by way of a reminder that Mexico would not pay for it. It seemed Trump might be forced to give a tad on a signature issue.

That is, until Wednesday night in Arizona.

"We will build a great wall along the southern border, and Mexico will pay for the wall," Trump said. "They don't know it yet."

His visit to Mexico and his apparent new tone initially seemed to rattle the Clinton camp. She hasn't responded to an invitation to visit Pena Nieto, and she blasted Trump's visit as "a photo op" in pointing out that diplomacy requires "consistency and reliability."

"We won't get another opportunity. It will be too late," Trump warned.

Trump has long said he's capable of changing, and he has proved that point over time. But on a core issue that vaulted him to prominence — that powered his unlikely rise through the primaries and to the nomination — he has shown that he's sticking with what got him this far.