Lebanon 1958 gets bloody and boggy? OTL US Marines got in and out without killing anybody or losing anybody. What if it turns into a prolonged proxy fight?
I can see this get ugly if done wrong.
Possible, but from what I've read Eisenhower was pretty determined not to get US troops involved long term in Lebanon.
Over a decade ago on SHWI, a poster named Chet Arthur broached an idea called "Lebanon, 1958" it was a pretty good discussion thread. Here:
https://tinyurl.com/y9cu9bqm
Thinking on that scenario, I see a couple long-term effects. Small scale manufacturing and tourism are boosted in the eastern Mediterranean (Greece, Turkey, Lebanon, Israel) and southern Italy by the presence of a sizable US troop contingent and the need to support it, much like how the Korean War and Vietnam Wars boosted East Asian economies.
Lebanon intervention will also see a lot of war brides and social connections established between Americans and Christian Lebanese (and Christian Palestinians). Americans and Muslims by contrast will hardly mix. By the 1970s and 80s or so this will have a major effect of increasing emigration from those groups and tilting the demographic balances even more towards Muslims in the region, as war brides, family unification and chain migration to the U.S. build up momentum.
Of course complicating factors in a ground intervention in Lebanon that gets big. For instance a bombing campaign against sources of adversary support in Syria is a near certainty, with even ground incursions a la Cambodia or an outright U.S. invasion to Damascus a possibility. Bombing campaigns or harbor mining might reach even further if the U.S. decides it needs to go after Egypt and Iraq as sources of adversary supply, but at that point things would seem to be widening way too much probably.