Cambodia certainly isnt anti-Vietnamese by any strech of imagination, but you can hardly say that Cambodia remains in Vietnam's sphere of influence.
Why? Just because Vietnam doesn't station troops there? Having troops stationed in a country is by no means the only way to have a sphere of influence. The US doesn't have troops in most of Latin America but few would say that Latin America isn't influenced by the US to some degree.
As of 2010 Vietnam was both in the top 5 export partners and top 5 import partners for Cambodia. And both are in ASEAN (note that Vietnam got into ASEAN before Cambodia).
Its not even socialist anymore or an ally of Vietnam, which definitely would not have happened if they remained in Vietnam's SoI.
Not socialist? Yet run by socialists since the 1970s....
Saying the interests of the CPP is the same as the interests of Vietnam is inaccurate.
I never once wrote that.
I pointed out that the CPP is basically the KPRP with a new name and the KPRP just happens to have been the governing party during Vietnam's presence in Cambodia. Additionally I pointed out that the CPP is not anti-Vietnamese. Just because they are not anti-Vietnamese doesn't mean they follow Hanoi's every wish anymore than the Conservative Party in Britain is going to follow Obama (or Romney's) every command even though the Conservatives are not anti-American.
But since you bring it up, I'm sure the CPP and Vietnam share many interests: a peaceful and stable Cambodia; good relations between the two; security concerns against piracy in the South China Sea and around Indonesia; increasing trade between the two; having a good border between both nations based on the current borders and not on some wild claims like those of the Khmer Rouge
Vietnam was fighting for the benefit of Vietnam and the advancement of the socialist cause, with the KPRP existing as an extension of that.
Really? That must have been a different war. The war I'm thinking of had Vietnam fighting with the very clear aim of removing the Khmer Rouge from power and keeping them from returning so that Cambodia would no longer be a hinderance. They accomplished that mission.
The CPP got a victory in the end, Vietnam did not. And while the CPP is the direct descendent of the KPRP, it is not the same as the KPRP Vietnam created.
So even though Hun Sen was prime minister when it was the KPRP and is prime minister now when it is the CPP and the membership of the CPP is basically the same as the KPRP then the CPP is not the same as the KPRP?

So more or less the same people with the same general socialist principles (and the CPP is still quite socialist) but the CPP is not the same as the KPRP?
Neither is the Kingdom of Cambodia the same as PRK.
And notice the kingdom there. The Khmer Rouge may have faded into obscurity but the neutral rebel groups were not defeated ether.
Instead they were basically co-opted into power-sharing. And the idea that Vietnam originally proposed in the 1980s (for a peace settlement involving all parties except the Khmer Rouge) eventually came to pass by 1994 as the Khmer Rouge were outlawed for breaking the peace agreement negotiated in the 1990s and were thus excluded (the Khmer Rouge didn't even bother to contest elections and thus never entered into government). So now we have a kingdom where the socialists are in the majority in parliament and have been in power uninterrupted from before the kingdom was restored AND all of this in a country where a
prince (Sihanouk) was head of state during one of the country's phases as a republic. A prince (later king) who by the way
in the 1960s "made many speeches calling the triumph of Communism in Southeast Asia inevitable and suggesting Maoist ideas were worthy of emulation".
You seem to be missing my point though that Vietnam was far less concerned about the other rebel groups to begin with except insofar as those other rebel groups had allied themselves with the Khmer Rouge. It was Vietnam which suggested in the mid-1980s that they ditch the Khmer Rouge so that all sides (except the Khmer Rouge) could arrive at a peace agreement. If they were really worried about the other rebel groups being as anti-Vietnamese and inimical to Vietnam's overall interest they wouldn't even have entertained the thought of this kind of deal. They only relented on the exclusion of the Khmer Rouge from the peace deal when the money began to dry up, but even then it worked out for them in the end since the Khmer Rouge once again shot themselves in the foot by not playing ball and refusing to register for elections and refusing to lay down their arms.
Considering the end result, all in all i dont see how its possible to classify Cambodia as a Vietnamese success in the long run.
Wait, what? How?
A country which no longer claims Kampuchea Krom/Cochinchina and which no longer initiates border incidents and raids and expels or kills the Vietnamese minority in Cambodia and which maintains friendly relations and important trade relations to this day (compared to the virtual state of war that existed from 1975-1979) is not a Vietnamese success? And all of this without the need anymore for Vietnamese soldiers to be stationed in Cambodia in order to ensure this state of affairs? And with the Khmer Rouge (the outright enemy of Vietnam) having been outlawed and eventually dissolving itself? All while the set of people that Vietnam helped to install into power remain there?
How is that not success based on Vietnam's original mission in Cambodia?
Sure they don't have a state following the exact model of Vietnam but the majority of Vietnam's aims in Cambodia were fulfilled. If the majority of the aims were met, how is this not success?
Let's compare that to what happened in Vietnam and Afghanistan:
- the US withdrew from Vietnam and the people who were in power with the help of American power did not remain in any position of authority (only lasting a few more years). Instead their Number 1 enemy (Vietnamese communists) came to power. Vietnam and the US had terrible diplomatic and trading relations for just over two
decades after this withdrawal. The enemy of the US in Vietnam (the Communist Party of Vietnam) did not dissolve eventually after the withdrawal but remains in power today.
- The Soviets withdrew from Afghanistan and the people who were in power with the help of American power did not remain in any position of authority (only lasting a few more years). Instead their Number 1 enemy (Mujahideen factions) came to power. Afghanistan and the USSR's successor basically had very cool diplomatic relations for just over a
decade after this withdrawal.
Especially with all the trouble the VPA went through to thoroughly destroy the goodwill they had with the Cambodian people.
And yet even today quite a few Cambodians view the invasion as a liberation and Vietnamese Cambodians are not being killed as was the case under the Khmer Rouge.....