prepositions - Omission of “that” (in this text)

I'm trying to re-write published newspaper articles for practice writing.

The original reads:

We seem to forget that we all have some rights over the government. The government has come into being primarily to serve the needs of the citizen, which he as an individual or as a member of a small community cannot take care. It is important we have an accountable government.

I wrote:

We seem to forget that we all have some rights over the government. The government came* into being primarily to serve the needs of a citizen, which he as an individual or as a member of a small community cannot take care. It is important that we have an accountable government.

I really don't understand why "that" is correct the first sentence and not second?