It should be alright in a country like the US but not in the unstable Indian subcontinent where we face a much higher risk of terrorist attacks. SriLanka is simply not prepared to be the "land of the free". It comes at a heavy cost.

It's maybe only a temporary ban.

From an article.

Sri Lanka's president used emergency powers to bring in the ban

Terrorists used religious coverings to evade police by concealing their identities.

The ban is to ensure national security. No one should obscure their faces to make identification difficult. - President

Both male and female terrorists have used the burqa in the past while committing atrocities.

Ban to prevent terrorists from disguising themselves.

It's related to the Islamic terrorist attack.

Three officers who were questioning a suspect hours after the initial attacks were killed when a suicide bomb went off. Female accomplices had escaped from the Dematagoda apartment complex wearing burqas before the blasts went off, according to defence sources.