Discontinuities are almost invariably of less consequence than commentators make them out to be. That having been said, Ferguson's is a somewhat dodgy argument.

-The Republican admiration for Harry Truman to which he makes reference is derived from Truman's diplomatic and military initiatives, not from any component of his domestic policy (much less a health care plan which was never enacted).

- I think if you did a content analysis of the verbiage directed against B. Clinton from the opposition, the bulk concerned B. Clinton's political past and his deficiencies as a human being and the attendant degradation of public life, not questions of public policy. ( I do not think it an accident that the example of rhetorical excess on policy he offers was from a news conference called in December 1993). He also neglects to mention that in 1993 there were those within the Democratic Party (e.g. R.M. Kaus) perturbed by the influence of Mrs. Clinton and the incestuous relationship between the Administration and the media.

-An analogy between the reaction to Clinton and the reaction to his two immediate successors cannot hold because Clinton's essential grossness is not replicated by either of them or any but a few of Clinton's predecessors. It was replicated by Lyndon Johnson and John Kennedy (in spades!), but the press in general covered for them (while only the broadcast media would cover for Clinton).

-Obama is compared unfavorably to Clinton because the policies followed are objectively more problematic.

-The animosity directed at G.W. Bush antedated the emergence of troublesome questions about the Iraq War in 2004. G.W. Bush was not a rhetorically confrontational politician and his preferences on policy were more heir to the strand of thought represented by Thomas Dewey than that represented by Barry Goldwater. It was all very curious.

AD, regarding Truman, it is worth keeping in mind that Truman wasn't all that far from Obama on health care policy and that was is some ways well to the left of Obama (wage and price controls.) No doubt there are plenty of ways that Truman would be considered way to the right of Obama on social issues and (I don't know, but suspect) conditions on government aid to the healthy and working aged. Like with Obama, it depends on what you choose to look at.

The animosity towards G.W. Bush follows a familiar pattern for politicians identified with the conservative wing of the Republican Party (for Bush, this identity was largely formed through the nomination fioght with McCain and his focus on Reaganite-type tax cutting arguments.) The pattern is that the current conservative figure is the worstest, most radical conservative of similar stature ever. Goldwater was worse that Bob Taft (Taft was for public housing don'tcha know), Reagan was worse than Goldwater (Goldwater was eventually pro-choice on abortion and had spats with the Religious Right), Gingrich was worse than Reagan (Reagan and Tip O'Neil got along so awesome and Reagan didn't try to cut Medicare), and G.W. Bush was worse than Reagan (Bush was a corporate dummy who stole the election.) There are of course the ever-present Hitler comparisons.

regarding Truman, it is worth keeping in mind that Truman wasn't all that far from Obama on health care policy and that was is some ways well to the left of Obama (wage and price controls.)

Again, that is not the aspect of the Truman Administration which is retrospectively admired by Republicans &c.

The animosity towards G.W. Bush follows a familiar pattern for politicians identified with the conservative wing of the Republican Party

There is no 'conservative wing of the Republican Party' anymore. There is a haphazardly libertarian wing (Christine Todd Whitman, et al) which might constitute ~20% of the total and the palaeosectaries who might constitute 5%. Messrs. Bush and McCain both were manifestations of the main body of the Republican Party, conventionally deemed 'conservative'.

I was around and about in 1980. I do not recall people comparing Mr. Reagan unfavorably to Mr. Goldwater. Robert Taft represented a mix of preferences that was almost completely absent from American political life from about 1959 to about 1990.

AD,

On Truman, it does tell us something that conservatives in the late 1970s onwards chose to almost exclusively focus on Truman as a patriotic and confident hawk rather than as a hyperpartisan economic radical (David Frum was an exception here) much less an enable of Communists in sensitive government positions. In the same way that it would tell us something about changing conservative views of Obama if, twenty years from now he was being called a responsible patriot who (based on the slow drawdown in Iraq and the surge in Afghanistan) was comfortable with on the use of military force unlike today's Democrats with their long hair and their Rock N' Roll. Such a view wouldn't be totally irreconcilable with contemporary arguments about Obama being post-American, a socialist radical etc. but...

On Bush and the conservative wing. What mattered was that Bush was identified (by liberals and by many conservatives) as being a conservative rather than a moderate Republican. Part of that process of identification was chronicled by Andrew Busch and James Ceasar in THE PERFECT TIE. Once made that identification has a certain subjective quality but facts can be tortured to fit the narrative. There are of course limits to this. If Bush had come out for abortion and tax hikes to go along with his spending increases, he would still have been stupid and out-of-touch (he was a Republican after all and spending by Republicans - at whatever level - forms the baseline for inhumanity), but he wouldn't have been the worst ever conservative until the next one.

On Taft and Goldwater: Rick Perlstein's BEFORE THE STORM, includes a section on how opportunistic (and perhaps sincere) liberals developed a retrospective affection for Taft as opposed to the radicalism of Goldwater.

On Goldwater and Reagan: In 1980 Goldwater was cagey about abortion as he needed pro-lifers to win his last Senate race (which he did barely win in that Republican-leaning year.) He came out as pro-choice and anti-Religious Right later. I was a kid for most of the 1980s, but I can remember the stories about the horrible authoritarian, turn conservatism had taken since Goldwater's day.

On Truman, it does tell us something that conservatives in the late 1970s onwards chose to almost exclusively focus on Truman as a patriotic and confident hawk rather than as a hyperpartisan economic radical (David Frum was an exception here) much less an enable of Communists in sensitive government positions.

He was not an 'economic radical'. Wage and price controls were extant public policy at the time Truman took office in 1945. The country suffered serious inflation until the close of the Korean War, which is why there was a residual interest in them. Wage and price controls are bad policy but they were not comprehensively eschewed by the Republican Party until after 1973.

To accuse Truman of 'enabling the infiltration of Communists, &c.' is an asinine libel. Quite apart from the question of the degree to which you would hold the president responsible for deficient counter-espionage capacity (given that there was no civilian intelligence agency in existence prior to 1942), the big pinecones spying for Soviet Russia (Alger Hiss, Harry Dexter White, Lauchlin Currie, and Lawrence Duggan) were appointees of the previous administration.

Again, the principal disputes on social and cultural questions ca. 1948 concerned race relations, with regard to which Truman and the Republican congressional caucus were not antagonists.

The main body of both political parties supported a policy of international engagement (treaties of alliance, military buildup, regional warfare, and economic aid abroad) after 1946. Perhaps a quarter of the Republican Congressional caucus (including Robert Taft) adhered to inter-war isolationism, but this strand of thought had dissipated by 1959. There was a small popular front faction in the Democratic Party, but it evaporated at the start of the Korean War. The context of the retrospective admiration for Truman was inter-party disputes over the military and foreign policy that had no analogue in Truman's day. By the way, what we can surmise about Obama's decision-making with regard to the wars in the near east and central asia is that it is driven by petty domestic political calculation; not the case with Truman.

What mattered was that Bush was identified (by liberals and by many conservatives) as being a conservative rather than a moderate Republican.

I do not know why you find yourself competent to declare that sort of thing ex cathedra. In any case, all of the candidates who competed worth a damn for the Republican presidential nomination after 1980 were derived from the main body of the Republican Party as regards their general policy preferences, bar two: Patrick J. Buchanan and Ron Paul. The one most proximate to Christine Todd Whitman in his stated preferences might be Steve Forbes. Since Mr. Forbes publicly chastised Princeton University for hiring Peter Singer, I do not think he quite qualifies.

Messrs. Reagan and Goldwater offered as an ultimate and distant goal the re-construction of the status quo ante 1929, something their successors have not. All of their successors (bar Buchanan and Paul) have been public advocates of international engagement, the retention of conventional behavioral standards and ideals, and greater resistance (than the opposition) to state intervention in economic life. They may be bloody hypocrites (and one suspects that many among the Republican establishment hold to common-and-garden professional class attitudes on these subjects), but they are not William Weld. Bush is identified as a 'conservative'? They all are.

Within that set of politicians, Bush conjured and ran on a significant expansion of the welfare state, like it or lump it. That has not been universal in Republican presidential politics. It is also difficult to think of a competitor at that level who has been less rhetorically confrontational. (Mitt Romney, perhaps). The animosity toward Bush has been something rather atavistic and indicative of an impulse within the Democratic Party that does not accept the legitimacy of any opposition whatsoever.

AD, on Truman, I don't think that Truman was a communist in government enabler, but examining the rhetoric of conservative (or merely very partisan) Republicans about Truman's security and foreign policies in the late 40s and early 50 with that of conservatives about Truman from the 1970s onwards might go to Ferguson's point about how partisan passions might lead to grotesque exaggerations in the moment. On the other hand alot of 1970s conservatives had been Truman Democrats.

You are of course right that across the board wage and price controls had been a live option in American politics up to the 1970s (just like some variation of government-run health care -Truman's would likely have quickly developed into a single-payer plan - had been an on-and-off again staple of liberal Democratic politics.) It goes to the question of how radical Obama is to support a plan that will get us to single-payer (complaints about the dishonesty and lousy design of the plan aside.) It also makes one wonder about the reaction if Obama came out for wage and price controls in the health care sector. I suspect he would be called a radical (aside from very, very unwise) regardless of the experiences of Truman and Nixon.

On Bush: The perception of Bush as conservative and supported by self-identifying conservatives in Republican primaries is covered by Busch and Ceaser. The identification is important (and liberals, from my reading considered Bush to be conservative if not radical) in understanding the reaction. Bush wasn't seen as a "moderate" Republican (very unlikely that one of those, running on a Susan Collins-type platform would get nominated) or even a patrician uncomfortable with ideology (like G. H. W. Bush.) For purposes of demonization (which I suspect is somewhat sincere), only the identification as the tribal/ideological "other" matters (there has to be some limited basis in reality, it wouldn't have worked if Bush had been a pro-choice tax raiser). The facts can then be either tortured on ignored according to how they serve the thesis.

For an example of how an infected mind operates there is this gem from Jon Chait https://www.tnr.com/blog/jonathan-chait/78458/obama-the-non-radical