In Donald Trump's America, you might never expect a Republican senator to freely admit to a history of harboring undocumented immigrants.

But that's effectively what Sen. Jeff Flake has done, recalling his life before politics farming and ranching in northern Arizona in a new book published Tuesday by Random House.

"My life was made far more difficult during the middle of summer when the Border Patrol would raid our farm. Sometimes the Border Patrol would send small planes to search our alfalfa fields for migrants," Flake writes. "When I would hear the distinctive whine of the Cessna, I'd hop on a horse, put on a hat that would obscure my head, and try to divert the Border Patrol away from our workers — a decoy in the game of cat and mouse."

Flake was, of course, a member of the bipartisan "Gang of Eight" which crafted an overhaul of federal immigration laws that passed the Senate only to see inaction in the House.

It's against that backdrop that Flake, who faces voters again in 2018, makes his case for how the Republican Party came to be taken over by Trump and a mixture of nationalism and populism.

The crux of "Conscience of a Conservative" — named just as the 1960 work by another Arizonan, Sen. Barry Goldwater was — is criticism of Trump and not exactly veiled shots at GOP leaders like Speaker Paul D. Ryan of Wisconsin and Senate Majority Leader Mitch McConnell of Kentucky who it seems in Flake's view acted as enablers.

But it is Flake's self-reflection that is perhaps most insightful. A true conservative and Goldwater disciple, the senator regrets voting against bailing out Wall Street back in 2008.

Flake publishes a contemporaneous diary entry about how GOP presidential candidate Sen. John McCain was lobbying for his vote, and how he rejected that entreaty.

"TARP was actually a modest price to pay to forestall a global depression. My vote against the bill is a vote that I still regret. That the vote did not hurt me politically is immaterial. That the bill was attacked from both right and left, and as a matter of policy was deeply flawed, is beside the point," Flake writes. "Here's what mattered: At a moment of national and global crisis, that vote was an abdication of my responsibility as a member of Congress."

With the benefit of hindsight, Flake says he should have viewed the House votes on the Troubled Asset Relief Program much differently from the establishment of the Medicare prescription drug benefit back in 2003.

"My TARP vote was more an act of cowardice than conscience. I knew what needed to be done. I just left it up to my colleagues to do it."

Flake was revising his new book right up until publication, as indicated by a scene from a hospital waiting room on the day of the shooting at the Republican practice for the Congressional Baseball Game.

"It seems elementary to have to form this thought, much less write these sentences, but here we are: I am a proud conservative and a lifelong Republican," Flake writes. "That does not make the Democrats my enemies. America has too many real enemies to indulge such nonsense."

Flake self-identifies as a Goldwater conservative. Before he came to the House of Representatives, he ran the late senator's institute in Phoenix.

In the House, the current junior senator from Arizona was often a thorn in the side of leadership, and in particular of members of the Appropriations Committee, with what seemed at times like a quixotic crusade to single out earmarks with amendments on the floor.

The only reference Flake makes to now-disgraced former Speaker J. Dennis Hastert is in a story about a time Flake forced a vote on stripping a Hastert earmark, even after being informed by a journalist that the Illinois project originated with the speaker.

"Perhaps because I was naive, it never occurred to me to not do what I thought was right just because my opponent in that instance was a member of my own party, not to mention the most powerful member of the House of Representatives," Flake writes.

Among GOP congressional leaders criticized by name, Flake has perhaps no stronger words than for Newt Gingrich and Tom DeLay.

In speaking of DeLay, Flake dives into the corruption of his era as a member of House leadership, but the shot at Gingrich is perhaps even more biting.

"Donald Trump is not the source code for our obsession with the politics of personal destruction," writes Flake. "Our crisis has many fathers. Among them is Newt Gingrich, the modern progenitor of that school of politics. Any honest accounting of how we got to this new day has to reckon with Newt, whose talent for politics exceeded his interest in governing."

As in the excerpt published Monday by Politico, Flake criticizes himself for being among the GOP lawmakers who opted to at times avoid responding to Trump's tweets, saying it could consume all of his time.

"Given the volume and velocity of tweets from both the Trump campaign and then the White House, this was certainly true. But it was also a monumental dodge. It would be like Noah saying, 'If I spent all my time obsessing about the coming flood, there would be little time for anything else,'" Flake writes "At a certain point, if one is being honest, the flood becomes the thing that is most worthy of attention. At a certain point, it might be time to build an ark."