This is a link to a news article about CP's possible interest in a take over of Norfolk Southern:
http://www.bloomberg.com/news/articles/2015-11-09/canadian-pacific-said-to-explore-takeover-of-norfolk-southern
It would be a monoply and I think the government would say no.
Monopoly implies exclusive control, and given CN and CSX would still be competition, that's not a monopoly.
Here's a helpful link to more information about monopolies.
http://lmgtfy.com/?q=definition+of+monopoly
-Chip :)
I doubt it'll happen. Obama hates railroads (excepting Buffett Northern) so the DOJ will thumbs-down any merger. Similar to airlines, where none of the big four will ever be allowed to merge with any other member.
If, due to the war on coal, NS or CSX is so weak by the time the next administration tekes over, a GOP leadership might allow a western road to swoop in. And both eastern roads will go at once to their respective western overlords, just like the mergers that formed CSX and NS.
NS is so strong in other area's of the frieght bussiness, a complete loss of coal{which won't happen} would be a drop in the bucket as far as revenue.
Freight patterns are always changing.