Evils in Hinduism 2 - Marrying Foreigners is Prohibited

No, the Dharma Shastras explicitly forbid Hindus from marrying foreigners, otherwise known as Mlecchas.

Here are some verses from the Atri Smriti that prohibit interracial marriages:

1. The purification for knowing [having sex with] a Mleccha woman consists in a Santapanam penance, or it is said, one may attain to purification by performing a Taptakrcchra penance.
2. If a person lives with a wife known [who has had sex with] by a Mleccha man, he becomes purified by bathing with the cloth on and drinking clarified butter.
3. By cohabiting [living with and having sex with], unknowingly, with the women of the Chandalas, Mlecchas ... one is purified by a Paraka.
4. But if one knows them willingly, and procreates children with them, then he is degraded to the same caste as them; there is no doubt about it, for that man is born as her son.

So it is actually a huge sin to marry foreigners, since one becomes degraded to the caste of Mleccha.

This answer explains some of the different types of penances for sins.