Actually Trump has pulled back several times - a consistent problem with him when dealing with Iran...
...until faced with impeachment and now removal in the Senate.
Now, it's a completely different story. Conservatives wanted a strike on an Iranian asset in order to secure a non-removal in the Senate. Just more Republican quid pro quo for you.
Like the vast majority of the country, "Conservatives" had no idea we were about to strike Soleimani until we did it. Those who were
part of the strike may tend to lean conservative, but include representatives from both major political leans.
As for the idea that Trump would have otherwise been removed by the Republican-dominated Senate
.... that a supermajority
of that body was ready to vote for removal and simply failed to mention this... only changing their minds Because Soleimani.... I find that... shall we say, exceedingly
unlikely, though I would love to see any citation you can provide that a majority of Republican
Senators were ready to remove the President prior to the strike.
The strike on Solemani has had no appreciable effect on impeachment proceedings, which were previously not going to result in removal, and which are still not going to result in removal.