I'm no lawyer, so I had to do some re-reading, and searching for legal definitions.
There were serious attempts to obstruct the Mueller investigation.
Trump, and others, are criminals. The evidence is in the report.

It's important to know exactly who this character is , and why he does what he does.

https://en.wikipedia.org/wiki/William_Barr

Of course, the GOP won't convict. That's not as important as one may think.

Impeachment inquiry and proceedings will bring a lot of information to light.
The public will learn more and more about the criminality of Trump as the proceedings go on.
There will be damning evidence for all to see. The GOP will have to face the public.
At the same time, Trump, GOP Sens, and GOP Reps will have to try and run a campaign for re-election.
The press will hound the WH, and the Republicans. Major chaos, any way you look at it.
Once all the evidence is in the public's ears and eyes, the GOP will have this choice ---
Convict Trump, or attempt to convince an angry nation why they shouldn't.

https://www.washingtonexaminer.com/news/white-house/rolling-thunder-chief-predicts-biker-descent-on-dc-if-dems-impeach-trump?fbclid=IwAR3_6WSFtSWN_NalsPvIpyBh-s_eLdBatkC3Ere05tWEunfM8CRmAPrp2KI

Why would anyone risk their career over Trump? Trump is temporary, and only one person.
Right wingers wouldn't think twice about hanging one person out to dry.
Trump is a puppet. We need to cut off the hands of the puppeteers.
There is much more at stake here than the WH. The Mueller Report is being suppressed
to prevent further investigation which would expose a lot of nasty shit, and a lot of people.

Those involved in this coup need to be exposed and dealt with very, very harshly.

is caused by fear of the "civil war" we've been promised by some trumpists
if he's impeached?
I hope the House isn't intimidated by the right wing militia monkeys.
I know I'm not.

can the House subpoena him to get him to testify?

Asking for a friend...

of our elections, I will never believe that Trump cares about it, as he claims.

the "freedom of the press"?
They are not the press. They are a PR agency, at best, and filthy traitors, at worst.
I think they're dangerous enemies of the United States, and believe they should be treated as such.