There are underground ML orgs in the US already. The problem is, the workers are still disorganized. And with gig economy growing in the share of the whole job market, the problem is only getting worse.

I do agree that you need a strong cohesive organization and for that you need a clear political line. However this habit of ideological purity fetish that is common to all ML, Trot or Maoist orgs has also led to an immense fragmentation that made organizing in the mass scale impossible. Even worse, it made the Marxist parties irrelevant in the dispute over public subjectivity.

While I don't question that Lenin's methods worked in Tsarist Russia, specially because they achieved a revolution there (praxis), we need to understand that at Lenin's time political organizations (even bourgeois ones) were strictly forbidden. It means that carrying activities underground was not simply a choice, but a response to their historical material conditions. Even Lenin, before building the Russian social democratic party, participated in an adventurist org before so he also had experience in doing so. Today, even though we can't let our guards down because repression by state forces is still a very real thing, the conditions are not the same.

I see a lot of orgs trying to replicate the Bolshevik's physical newspaper, and even though I think this kind of effort has its merits, nobody reads physical newspapers anymore. So most of the time see purists as HEMA practicioners trying to hone their swordsmanship skills based on old manuals. The problem is that HEMA practicioners don't take themselves very seriously (and they know it's a historical re-enactment, not a practical skill for today's needs) while some purist orgs still think they are doing the real thing.

Instead of just thinking on replicating what the Bolsheviks did, why don't we instead think on the objectives we want to achieve? The real merit of Bolshevik organization was that they were able to create a big network of Bolshevik chapters around Russia, and create an organized propaganda and information gathering apparatus. Not only that, but they were able to fund their operations to a point were people could be dedicated revolutionaries, not simply amateurish voluntaries whose revolutionary work was the fourth priority in their lives.

So even though the Bolsheviks strived for a very clear political line, I disagree with the view that they were extremely factionalists. After the 1905 revolution they even became more open and accepted more proletarian members, they didn't stick with just a small cadre of die hard intellectuals. And they had to do this otherwise the other orgs (Memsheviks and SRs) would become more important than them.