There are techniques of Buddhism, such as meditation, that anyone can adopt. And, of course, there are Christian monks and nuns who already use Buddhist methods in order to develop their devotion, compassion, and ability to forgive.
The way of presentation is different according to each religion. In theistic religions like Buddhism, Buddhist values are incorporated. In nontheistic religions, like some types of ancient Indian thought, the law of karma applies. If you do something good, you get a good result. Now, what we need is a way to educate nonbelievers. These nonbelievers may be critical of all religions, but they should be decent at heart.
Whatever we once were, we are no longer just a Christian nation; we are also a Jewish nation, a Muslim nation, a Buddhist nation, a Hindu nation, and a nation of nonbelievers.
Hinduism threw away Buddhism after taking its sap. The attempt of all the Southern Acharyas was to effect a reconciliation between the two. Shankaracharya's teaching shows the influence of Buddhism. His disciples perverted his teaching and carried it to such an extreme point that some of the later reformers were right in calling the Acharya's followers "crypto-buddhists".