I think they will try the problems is that since this is before the Suez Crisis but also somewhat after WW2.
The French may try to fight Vietnam as before the Suez Crisis the Imperial Powers ( UK and France, France mainly ) really have no interest in losing their colonies and until the Suez Crisis they still considered themselves as entitled to their colonies.
On the other hand they lost their entire force in the French-Indochina war and will be hard pressed to replace their expeditionary forces in addition to losing all their collaborators in Vietnam
Similar to the US, Vietnam can send a diplomatic mission to France; accompanied by the French ambassador, who can explain very clearly that if France couldn't even win against Việt Minh guerrillas in 1954, then there's no way in hell that it could win against 2020 Vietnam
after losing most of the Far East Expeditionary Corps.
Of course, appeasing the raging ego that is Charles de Gaulle will be...difficult, but not impossible. If the French government can accept that Indochina was effectively lost as soon as the ISOT happened, then Vietnam can offer them uptime knowledge and favourable economic incentives; in exchange for political recognition, the peaceful withdrawal of French forces from Laos and Cambodia, and the creation of a transitional administration to prepare both for independence.
Speaking of French Indochina they in my opinion at least will probably focus on holding Cambodia as the last bastion of actual colonial development in there hands to wait for reinforcements as holding Laos is frankly untenable and will just get encircled and stuck between Vietnam and neutral Siam.
Vietnam won't make a move on what's left of French Indochina, unless some trigger-happy Frenchman fires first; the CPV will try their best to get a peaceful settlement with Paris. But if war breaks out, even consolidating forces in Cambodia won't work; Vietnam already invaded the country once, and some of the soldiers who fought in that war are now among the PAVN's leadership. It's just a matter of dusting off the old Khmer Rouge war plans, and adapting them to counter French deployments instead - which, of course, Vietnam is completely aware of through historical records.
Also, what happened to everyone in the original countries? Did they just go poof when the downstreamers showed up, or are they trying to figure out why there are suddenly skyscrapers in the country? Because if its the former, the French might be forced to go to war with downstream vietnam for killing whoever they had in the country before the ISOT happened to avoid backlash at home.
In a standard ISOT scenario? Yep, the downtime area goes poof - usually handwaved away as switching places with the uptime area, or transported to a virgin Earth. So yes, France has lost the lion's share of its Indochinese collaborators and military assets - what remains in Laos and Cambodia is completely inadequate against the PAVN.
China won't take any of this well and would be especially upset at having such a power as this Vietnam at China's vulnerable southern border where a lot of there good industry, economy, resource extraction, and even to degree agriculture is at. Southern China is just a generally rich part of China as far as valuable parts of China go so Mao will certainly be threatened and might try something but that would upset the soviets who would be trying there best to keep Vietnam neutral or even go back to proper communism so we might see a harder sino soviet split from that.
Had the ISOT happened in 1975, I would agree with the Sino-Soviet split being worsened by Vietnam. But this is 1950, where the Soviet Union and China remain firm allies bound by hardline Marxist orthodoxy; the Sino-Soviet Treaty of Friendship was just about to be signed in February 1950. They would both view Vietnam as a threat: China for obvious reasons, and the Soviet Union for offering an attractive, proven alternative to Stalinist poverty and repression.
After all, the OTL split was caused by de-Stalinisation and "peaceful coexistence"; if both Stalin and Mao successfully purge their enemies and further commit to totalitarian rule, relations would in all likelihood be considerably
strengthened, to Vietnam's detriment.
Still despite the frankly dark shit Mao has done to put it simply and not go down that rabbit hole he was not stupid so I dont see him outright invading Vietnam unless he feels he can keep both America and the soviets from interveneing.
Their are multiple issues which might cause Mao to act erratically.
The first is simply the matter of legacy in that the PRC is Capitalist as someone who is a communist the fact that his legacy is a capitalist society means that there might be purges.
Another would be from his neighbors NK and Vietnam would be dangerous as they will check PRC influence by their mere existence and NK is very odd in that it may decide to try and do stupid shit as it has access to a nuclear program and rocketry but has difficulties in feeding its population.
He is unlikely to go after Vietnam immediately as the French are in full Empire mode as of now and Vietnam would try to dismantle French Indochina.
Interestingly, during the 1950s Mao's influence on the CCP hadn't become consolidated, as multiple internal cliques still existed after Chinese Civil War. It could be really interesting for the Soviet Union to learn about the Sino-Soviet split, the clown that is Khruschev, and Brezhnev who created institutionalized corruption. One thing is pretty sure that CPSU is gonna have a purge.
Yeah, having uptime history revealed to the Soviet and Chinese leadership is going to create political earthquakes. In the long term, the revelation of communism's ultimate failure will massively destabilise the global Communist movement; communist insurgencies across the globe will lose popular support, while far-left "useful idiot" movements in the West will be dealt a credibility death blow. Consider how Khrushchev's
Secret Speech denouncing Stalin
devastated the Western left and laid the foundations for reformist, democratic Eurocommunism - uptime revelations will have an impact
orders of magnitude greater.
Meanwhile, the
samizdat presses all but ensures that uptime history will eventually reach even the average Eastern bloc citizen; the widespread loss of faith in the Soviet system that presaged OTL 1991 will happen three decades earlier, which means that even the Soviet Union will eventually have to deal with the ramifications: democratise and liberalise, economic "
renovation" along Vietnamese lines, or dissolution once again? Further repression could only goes so far, especially when the prophesised "final victory" turned out to be such a laughable sham.
But in the short term, things are likely to get worse before they get better; the timing for our scenario is particularly bad. Stalin and Mao are still in power, and both are hardline ideologues who will stop any liberalisation dead in its tracks.
In the Soviet Union, a second Great Purge is inevitable; Lavrentiy Beria will have a field day rounding up anyone who even breathes the wrong way. With Stalin at the peak of his political powers, any resistance/coup efforts will probably fail, dooming the Soviet bloc to years of bloody repression. Stalin will likely put in place measures to preserve his personality cult, replacing purged CPSU cadres with hardliners and puppets, and prevent anything like the Khrushchev Thaw from reoccurring; which means that prospects for reform will be bleak even after his death.
China, on the other hand...it all depends on who gains reliable access to uptime records first, and which faction Vietnam and North Korea decides to back. If Mao gains the upper hand, then the Cultural Revolution is coming a decade early; the consequences for the Chinese people, economy and cultural heritage will be even more disastrous. Relations with Stalin's regime and North Korea will be greatly strengthened; conversely, a Sino-Vietnamese war becomes much more likely.
But since 1950 Mao is not nearly as all-powerful as Stalin, his rivals have more room for action. If any of Mao's opposing cliques, especially those who were purged or exiled in OTL (Deng Xiaoping, Liu Shaoqi, Zhou Enlai, Peng Dehuai, He Long, etc.) gains the upper hand, then frankly
anything could happen. Short-lived, failed rebellions? Successful anti-Mao coup putting reformers in charge? Full-on collapse into
Warlord Era 2: Electric Boogaloo? Take your pick.
The last scenario is Vietnam's geopolitical dream; I can foresee the CPV playing multiple sides to prevent any one faction from gaining the upper hand, with the ultimate aim being to ensure that China remains permanently divided between mutually hostile states. Countering North Korean influence is also a factor, as Vietnam will back reformist forces, while North Korea supports the hardliners. This could throw the Cold War's dynamic completely out of whack, greatly weakening the Communist bloc in the East.
TL;DR: Vietnamese economy is going downhill, but it has the potential to recover fully.
Yep, the initial hard crash is inevitable. But in the medium-term, how quickly Vietnam bounces back is dependent on how quickly it could reestablish supply chains (both energy and raw materials), as I've discussed in
my first post. This is why the CPV will exhaust all diplomatic measures before going to war with
anyone.
The tech downgrade is also inevitable, but it will be an uneven decline. Smartphones and computers will eventually break down, and advanced optics cannot be replaced; but Vietnam will do everything it can do to localise tech manufacturing, and many simpler electronics can still be produced. There is a small domestic integrated circuit manufacturer/research center, ICDREC, who can currently produce
180 nm- and
130 nm-process (1999-2001) semiconductors; this is around two decades behind the 5 nm chips of today. Of course, this is still lightyears ahead of anywhere else; but scaling up capacity to service the entire country is going to be an arduous task, likely not achievable in a reasonable timescale without considerable FDI inflows. After a decade, I expect Vietnamese computers and chipsets to be roughly around the 1990-2000s level.
This is also why aligning with the US will be more rewarding in the long run: Vietnam doesn't just needs resources and money, but
brainpower. Collaborating with the Western world's vibrant academia and corporate sector will deliver much greater long-term R&D gains than the Soviet bloc, which in 1950 was actually still
denouncing cybernetics as "reactionary pseudoscience"; Soviet computing in OTL only took off after the Khrushchev Thaw.