1. If five compentent guys with garands go up against five competent guys with AKs it's a slaughter; the guys with AKs will have fire superiority and they can carry more ammo so they can keep it up longer. The jungle even makes the Garand's longer effective range irrelevant. The guys with AKs can pin the other guys down, outflank and kill them. Absolutely no problem. 2. The American politicians of the 40-45 era were not magically more competent than those of 20 years later, I don't know what realistically could be expected to change there. I dunno what you're getting at with "political bullshit", politics is literally the only thing that matters. The actual shooting part is very much secondary to the eventual outcome. Look at the Germans in WW1 and 2, pretty good on a tactical level, still lost every time.
1. The AK is a Spray & Pray. Using it straight up 5 on 5 for suppressive fire will blow through the ammo carried in nothing flat. The Garand, was, is, and always will be, a better weapon in a set piece engagement than ANY assault weapon. Now, if the Marines have had to slog through 20 miles of bush, the additional weight of the weapon and the 30-06 ammo would be a factor, and if it is house to house fighting any combat rifle (including the AK) isn't an ideal tool, but as far as a pure combat weapon in a squad situation the M-1 isn't just better, its lightyear's better (the M-14 might be better still, but only in semi-auto mode or with troops trained to fire 2-3 round controlled bursts). Nothing replaces the lethality and firepower of a full sized round.
2. Politics in Vietnam was everything. The war was ALL politics and public opinion. In a way it was remarkably like the American Revolution in that manner. Washington had to keep from getting his army wiped out and play for time and for public (mostly merchant) opinion in England to wear the government's resolve down; Giap had to do the same thing except he was simply playing for time. The United States was not in a "war" in a conventional sense, unfortunately, Giap knew this while Washington never did really figure it out. In 1941-45 the formula would have been vastly different.
In the world of 1941-45, once the war started it would have been fought to simply destroy the North as a nation-state, had that been done in the 1960's the U.S. would have "won" before the end of 1967. Ho, Giap, and the rest of the North's leadership would have been obliterated, along with the ability of the North to engage in war of any kind (as an easy example, a WW II U.S. would have destroyed the Red River dikes and flooded a decent part of the North's productive land, and any trace of rail line in the North would have pounded to scrap in the same air offensive).
Now the politics and American public opinion of the Vietnam War would not have supported (rightly, IMO, I must hasten to add) that sort of blood-letting, but that sort of viewpoint evolved in the 20 or so years between the start of WW II and the start of American serious involvement in Viet Nam.