>>215939660 (OP)
What on earth would be the point of such a thing? Either end is thousands of kilometers away from any significant population center or place a person might want/need to go.
I enjoy border towns a lot, and like international infrastructure probably slightly more than the average person without autism—I love a footbridge across a border, for example. But a long dark tunnel between dark frozen wastelands doesn’t do it for me and feels like money poorly spent. I might support seasonal ferry service across the Bering Strait (assuming it’s ever ice free?), or perhaps even a China-style megabridge. But the tunnel idea doesn’t appeal to me at all, and wouldn’t even if it weren’t pointless.