Can MPTCP secure Internet communications from man-in-the-middle attacks?

Multipath communications at the Internet scale have been a myth for a long time, with no actual protocol being deployed so that multiple paths could be taken by a same connection on the way towards an Internet destination. Recently, the Multipath Transmission Control Protocol (MPTCP) extension has been standardized and is undergoing rapid adoption in many different use-cases, from mobile to fixed access networks, from data-centers to core networks. Among its major benefits — i.e., reliability thanks to backup path rerouting, throughput increase thanks to link aggregation, and confidentiality being more difficult to intercept a full connection — the latter has attracted lower attention. How effective would be to use MPTCP to exploit multiple Internet-scale paths and decrease the probability of Man-in-the-Middle (MITM) attacks is a question which we try to answer. By analyzing the Autonomous System (AS) level graph, we identify which countries and regions show a higher level of robustness against MITM AS-level attacks, for example due to core cable tapping or route hijacking practices.