Who Pays
The current problem with stem cell research is a typical one. Should the federal government be deciding whether or not stem cell research CAN be conducted in the first place AND who pays for it?
The federal government has NO BUSINESS deciding this issue, just like they have NO BUSINESS making decisions on abortion. In fact, if it weren't for the unconstitutional regulations on abortion there would be no issue.
As for who should PAY for scientific research - NOT taxpayers. Taxpayers should not be forced to pay for research (or art, or any other cultural aspect) that they 1) do not approve of 2) do not directly benefit from.