No, he most certainly did not. He frequently sided with the enviro-whackos. His endorsement of Kerry was what finally woke people up to the fact he was NOT committed to conservatism.
During the Smith-Sununu primary, I could easily name over a DOZEN issues where Sununu voted the "wrong" way, whereas the ENTIRE "Smith is a an envirowacko charge" came solely because he voted the "wrong" way on ONE issue, namely, ANWR drilling in Alaska. If you can come up with ANY other issue where Smith VOTED the wrong way, feel free to tell me, since the Sununu fan club was unable to do so in the primary.
Incidentially, the same crowd ranting and raving about Smith stabbing Bush in the back will demand we vote for Linc Chaffee (who also, much more vocally, refused to endorse Bush for re-election). Their hypocracy knows no bounds. Sort of like how they say it's terrible for Tancredo to "backstab" Republicans in Congress by suggesting Delay temporarily step aside, but when Arnold runs denouncing Republican leaders for impeaching Clinton or calling people "right-wing crazies" for trying to pass racial privacy laws, that's their idea of "loyality"