Republicans are being forced to Repeal and Replace in one fell swoop

In this way they cannot repeal without also replacing Obamacare. Also, in this way it is a pragmatic way for the whole party not to go extinct in 2018 during the next election cycle. So, I see the wisdom of designing this in this way. Also, it is considered a reconciliation plan and not a regular bill so therefore it can't be filibustered and only needs 51 votes to pass in the Senate.

But, the real problem here is Conservative Republicans are alreday against it, NO Democrats are going to vote for it at all, so even if it passes it will always be suspect to Democrats who will likely also destroy Trumpcare at some point in the future the way this partisan battle is going.

So, both Conservative Republicans and ALL Democrats likely aren't going to vote for it. But, here's the thing. Since Republicans never have agreed on anything ever regarding healthcare in history, if they cannot agree on this, Obamacare stays in force and in an emergency Trump could resend his Executive Order which castrated Obamacare when he first came into office and leave Obamacare in place until the Republicans can find some way to save face from their ridiculousness.