watasitati ha seigi wo mamoru.

It is read:

わたしたち は せいぎ を まもる。

Word by word:

• 私たち = わたしたち
• は = pronounced わ here
• 正義 = せいぎ
• を = pronounced お in modern Japanese
• 守る = まもる

When は is used as the topic particle, it is pronounced wa, not ha.

So in this sentence:

• 私たち = we
• は = topic marker, pronounced wa

This is one of the first pronunciation exceptions learners meet in Japanese. The spelling stays は, but the pronunciation changes because it is functioning as a particle.

Yes. 私たち means we, and たち is a common suffix used to make a pronoun refer to a group.

• 私 = I / me
• 私たち = we / us

However, Japanese does not always need an explicit plural marker the way English does. In many situations, Japanese can leave number vague if the context already makes it clear.

Also, たち does not work exactly like an English plural -s in every case. It is often used with people, especially pronouns.

は marks the topic of the sentence.

So 私たちは means something like:

• As for us, ...
• We, ...

In natural English, we usually just translate it as we.

This is an important point: は does not always mean the grammatical subject in the same way English does. It marks what the sentence is about. In this sentence, the topic is 私たち.

を marks the direct object of the verb.

Here:

• 正義 = justice
• を = marks justice as the thing being protected
• 守る = protect / defend / uphold

So 正義を守る means protect justice or uphold justice.

A very common pattern in Japanese is:

noun + を + verb

where the noun is the thing directly affected by the action.

Japanese basic sentence order is usually Subject/Topic – Object – Verb.

So:

• 私たち = we
• 正義を = justice + object marker
• 守る = protect

That gives:

私たちは正義を守る。

This is normal Japanese word order. Unlike English, the verb usually comes at the end of the sentence.

守る is in the plain non-past form.

In Japanese, the non-past can mean:

• present: we protect justice
• future: we will protect justice
• sometimes a more general or habitual idea: we stand for protecting justice / we uphold justice

The exact meaning depends on context. Japanese does not force you to choose between present and future as clearly as English often does.

It is plain style because the verb is 守る.

A polite version would be:

私たちは正義を守ります。

So:

• 守る = plain
• 守ります = polite

The plain form is very common in dictionaries, casual speech, slogans, fiction, and statements of principle.

守る often means:

• to protect
• to defend
• to safeguard
• to uphold
• to keep or observe in some contexts

With 正義, it often sounds more natural in English as protect justice, defend justice, or uphold justice.

So this is not necessarily only physical protection. It can also suggest standing up for justice as a principle.

Yes. Japanese often omits subjects or topics when they are understood from context.

So you could also say:

正義を守る。

That could mean:

• We protect justice
• I protect justice
• They protect justice
• or even something like Protect justice

depending on the situation.

Japanese frequently leaves out information that English normally states explicitly.

No. Normal Japanese writing usually does not use spaces between words.

So the standard written sentence is:

私たちは正義を守る。

The spaced version:

私たち　は　正義　を　守る。

is mainly for learners, readability, or teaching materials.

正義 is a real and common word, but it sounds a bit weighty or idealistic compared with very basic everyday vocabulary.

It often appears in contexts like:

• morality
• law
• hero stories
• political or philosophical discussion
• slogans

So 私たちは正義を守る。 can sound strong, dramatic, or like a mission statement, depending on context.

Yes, but the nuance changes.

• 私たちは正義を守る。 = As for us, we protect justice / a general statement about us
• 私たちが正義を守る。 = We are the ones who protect justice / more emphasis or contrast

So は presents 私たち as the topic, while が can put stronger focus on who is doing the action.

Both are grammatical, but they are not identical in feeling.