I actually posted something about this back in 2001:
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In this newsgroup, there has been discussion of all sorts of alternative
outcomes for the Russian Revolution--the February Revolution crushed and
the Tsar staying in power; the Provisional Government surviving; Kornilov
coming to power; the Whites winning the Civil War, etc. However, one
possibility I don't recall our having discussed is a Russia governed by the
Left Socialist Revolutionaries (Left SRs).
Oliver Radkey, one of the leading historians of the SRs, has noted that
"The martyrs of Social Revolutionism were more often than not the left
SR's, since they stayed and took it while other SR's were finding refuge in
Paris and in Prague. Their competition was peculiarly unwelcome to the
Bolsheviks because of the combination of genuine revolutionary fervor with
championship of the peasant cause. As a result, they were smashed by a
regime which always insisted on having its left flank clear..." *The Sickle
under the Hammer: The Russian Socialist Revolutionaries in the Early
Months of Soviet Rule* (New York and London: Columbia University Press
1963).
The Left SRs supported the October Revolution, they joined Sovnarkom as the
Bolsheviks' coalition partner (after first pressing unsuccessfully for a
coalition government of all the socialist parties), and they even approved
of the dispersal of the Constituent Assembly (in which they were poorly
represented, the lists of candidates having been decided on before the
"Lefts" had split off from the SR party). For all these reasons, they have
been condemned as being (until Brest-Litovsk) tools of the Bolsheviks. Yet
in fact they had numerous differences with the Bolsheviks: (1) The Left
SRs were a genuinely pro-peasant party; for the Bolsheviks, concessions to
the peasantry were at best a tactical matter until the peasants could be
proletarianized. (2) For the Left SRs, "all power to the soviets" meant
all power to genuinely independent soviets, not soviets manipulated from
above. (3) The Left SR People's Commissar of Justice, I. N. Steinberg was a
strong critic of the repressive methods of the Cheka, and did his best to
prevent an all-out Red Terror during his period in office. (OTOH, I am
skeptical of the claim of some supporters of the Left SRs that the only
reason the Left SRs stayed on in the Cheka even after the party had
withdrawn from Sovnarkom was to mitigate Bolshevik terror. At least one
historian, Alter L. Litvin, has concluded that "The presence of the Left
SRs in the Cheka did nothing to lessen the terror. An examination of the
minutes of the Cheka Presidium between January and June 1918 shows that the
Bolsheviks and Left SRs were unanimous in their decisions." Litvin, "The
Cheka," in Edward Acton, Vladimir Iu. Chernaev, and William G. Rosenberg,
*Critical Companion to the Russian Revolution 1914-1921* [Bloomington and
Indianapolis: Indiana UP 1997], p. 316)
The immediate occasion of the breach between the Left SRs and Bolsheviks
was Brest-Litovsk. The Left SR withdrawal from Sovnarkom has been
criticized as removing an obstacle to one-party dictatorship by the
Bolsheviks, but it boosted the Left SRs' popularity immensely. In the
spring of 1918, all sorts of opponents of the Bolsheviks and the treaty--
Left SR, SR, and Menshevik--made big gains in elections to the soviets.
The Left SRs with their heavy peasant support (in what was after all a
predominantly peasant country) thought they could achieve a majority at the
Fifth Congress of Soviets that would assemble on July 6, 1918. Between
April and the end of June, membership of the party went from 60,000 to
100,000.
Lenin, however, frustrated the Left SRs' plans by having Bolshevik-
organized "Committees of Poor Peasants" proclaim that they had the right to
represent at the Congress all those districts where local soviets had not
been "cleansed of kulak elements and had not delivered the amount of food
laid down in the requisitioning lists of the Committee of Poor Peasants."
(Quoted in Geoffrey Swain, *The Origins of the Russian Civil War*, p. 176)
This blatant manipulation assured the Bolsheviks of a majority at the Fifth
Congress of Soviets.
Deprived of their democratic majority, the Left SRs resorted to terror:
they assassinated the German ambassador, Mirbach, hoping that this would
force a renewal of the war. When Dzerzhinsky demanded that the assassins
be turned over for arrest, the Left SRs in the Cheka arrested him instead.
At this point the Left SRs could easily have seized power. They had 2,000
well-armed troops in Moscow, compared to 700 loyal to the regime. The bulk
of the Latvian Rifles, the only reliably pro-Bolshevik military unit in the
capital, were celebrating St. John's Day on the outskirts of Moscow, and
were unable to get back because of poor weather. Lenin was as defenseless
as Kerensky had been in October.
The Left SRs, however, did not press home their military advantage (by
seizing the Kremlin) largely because they did not really want to seize
power. What they wanted was to set off a popular uprising that would force
the resumption of the war. Just where the uprising would lead, they did
not know; they would leave that to the "revolutionary creativity of the
masses." In any event, the Bolsheviks were able to capture the Left SR
headquarters, liberate Dzerzhinsky, and arrest the Left SR Central
Committee.
Steinberg later said that the uprising had failed "not because [the]
leaders were not brave enough, but because it was not at all their purpose
to overthrow the government." Indeed, it is ridiculous to accuse Left SR
leaders like Maria Spiridinova of timidity. (As a 20 year old, she had
shot and killed a brutal Tsarist official, and was sentenced to death--
which however the Tsar commuted to life imprisonment. In 1937, arrested in
Stalin's Great Purge, she refused to yield to torture, and denied the
charges of "counterrevolutionary conspiracy." Sentenced to 25 years in
prison, she was shot in 1941.) The problem with Spiridinova, Kamkov (also
executed under Stalin) and other Left SR leaders was not lack of courage
but lack of political judgment.
Suppose the Left SRs had indeed successfully put through their own
"October" in July 1918--no nonsense about the "revolutionary creativity of
the masses"? There would be an immediate resumption of the war with the
Germans, but with the critical situation on the Western Front, the Germans
could hardly seize all of Russia, and if need be the new government could
retreat to the east. The new government would, at least at first, be very
popular with middle peasants, who resented grain requisitioning and the
"Committees of the Poor." Also, they might get the support of the
remaining pro-war Bolsheviks. The problem is that they did not have much
of a military force of their own. Would they be able to make common cause
with the Czechoslovak Legion and its Right SR allies? They would agree on
the war, but there were plenty of other things on which Left and Right SRs
still disagreed--in particular, rule by soviets versus the Constituent
Assembly.
https://www.alternatehistory.com/shwi/A Left SR Russia.txt
***
I'm not sure to what extent I would write that post differently today, but there are at least two things I would add:
First, I think I overestimated the unpopularity of Brest-Litovsk as a reason for the decline in Bolshevik support in elections to the soviets in the spring of 1918. The majority of the peasants probably welcomed the end of the war on any terms. What they resented about the Bolsheviks were grain requisitioning and the "Committees of the Poor."
Second, I am more inclined to believe now that the Left SR's might have been able to make common cause with the so-called Right SR's (as Oliver Radkey has noted, this is really a misnomer--some of them could better be classified as center or even center-left SR's) and Mensheviks. "A second factor in the Bolsheviks' decision to expel the Mensheviks and SRs from the CEC was a desire to prevent the formation of a united opposition against them. Their fears were justified: after the Left SRs broke with the Bolsheviks later that month, they and the Mensheviks adopted very similar positions on the Brest treaty, grain requisitioning, and the disbandment of soviets.. They also vehemently protested the establishment of the so-called committees of the poor in the villages, which were supposed to replace the unruly soviets. For the SRs and Left SRs, the fate of the peasant soviets they led was at stake. At the CEC session on June 11, Dan [a leading Menshevik] condemned the establishment of the committees of the poor. The Bolsheviks' plan to incite the poor peasants to confiscate grain from the more affluent ones, he warned, would trigger a bloodbath in the countryside. Dan specifically referred to his agreement "to a certain degree" with a similar criticism made by V. A. Karelin, a Left SR leader and also a member of the CEC, and until March 1918, people's commissar of state properties..." Vladimir N. Brovkin,
The Mensheviks After October: Socialist Opposition and the Rise of the Bolshevik Dictatorship,
https://books.google.com/books?id=cP0xLtu1aZgC&pg=PA225 Any disputes about the role of the soviets versus the Constituent Assembly would be of lesser importance if the soviets were no longer tools of the Bolsheviks.