TCP becomes unusable under interplanetary latencies; leaving the planet will force us to transition off of it.
But even if it is, TCP can be used with any latency if you configure the timeouts accordingly and maintain a large enough send buffer to allow retransmissions.
IP is usable to the Moon but a lot of protocols would need latency constants adjusted and very large packets would be desirable. Store and forward with custom replication protocols might still be more efficient for large volumes of data.