I'd have been fine with McVeigh being in prison for life instead of executed, but the backlash had Clinton commuted his sentence would likely have been substantial due to the severity of the crime.
Back when President Obama was still Senator Obama, he wrote he death penalty "does little to deter crime." But he supports capital punishment in cases "so heinous, so beyond the pale, that the community is justified in expressing the full measure of its outrage by meting out the ultimate punishment."
Abolish the Death Penalty: Barack Obama and the death penalty