If we're considering such scenarios, train shipping seems much more vulnerable to interruption. After all the tracks transit many states rather than just one or two.
If we're assuming that, say, Kazakhstan is the belligerent then yes.
If it's the United States then trains across central Asia are harder to stop and require bombing a third country (unlike a shipping blockade which just requires a threat and which doesnt require pissing off a third party).
Any nation would be hard-pressed to unilaterally close the Strait of Malacca. Pirates might occasionally delay or steal individual shipments, but I doubt even Malaysia and Indonesia could close it down together, if by some miracle they could agree to do so. Egypt would have a better chance closing Suez, but that's one of their few remaining sources of foreign cash so it would really hurt.
If for some reason USA wanted to stop a train, a few payments to the poorest dictator along the route would get it done. They wouldn't even have to stop anything permanently to make shipping much less reliable.
The US could probably close down the straits to commercial shipping with one carrier group.
The US could certainly make a few payments to a poor dictator in Central Asia to stop a train unless, of course, that country was reliant upon that train for the flow of critical goods, in which case it would take more than a few payments.
Haha you would have fit right in with both of the last two USA Presidential regimes. All tactics, no strategy. No thought for "the morning after". If USA tried that kind of bullshit with a "carrier group", USA would lose a few ships if it were lucky. China, India, and Russia would leap at the chance to mix it up offshore with the big bully, only this time with the "support" of the entire world except Israel and possibly UK.
If it's the United States then trains across central Asia are harder to stop and require bombing a third country (unlike a shipping blockade which just requires a threat and which doesnt require pissing off a third party).