Your understanding of American history is lacking. It was a group of Dems including LBJ in the senate who held up any advancement of civil rights for almost a hundred years. Republicans from Grant to Eisenhower were advocates of equality.
Yet they failed to act on it. Between 1860 and the Great Depression, Republicans controlled the White House and, at the same time, Congress more than half the time. Something about the blacks ought to be content with having the vote and businessmen didn't want to be forced to open up to blacks. Blaming inaction on the Democrats during that time is just more gaslighting from the current weird GOP.
Eisenhower entered office with a Republican majority in the House and control of the Senate. The two Civil Rights Bills passed in Ike's second term had support from the majority of Democrats in both Houses (most Southern Democrats holding out).
There also was a real threat of Communist infiltration of the government. The Russians had an extensive intelligence operation that had infiltrated many areas of the government because so many leftists in government were sympathetic to the cause. Academics, scientists and others actively provided information to the Soviets. All that has little to do with the point under discussion which was that the questioning of the government was once a leftist trait. LBJ was a favorite target of liberals even though he was a Democrat with the most liberal agenda until Biden. There would be no criticism of him under the modern liberals. They walk in lock step, Stasi-like compliance.
Richard does so well at seeing how he was once deluded and conned by the JFK Assassination Conspiracy mind-benders. Now Poor Richard has become all radicalized by the soul-sucking Fox News and alt-right-web echo chamber.
"Stasi-like" is the du jour dog-whistle at Fox since Trump stooge Jeffrey Clark used the term at a Jan-6th hearing last June. Now the Trump raid has inspired such effusive-though-inapplicable terms as "preemptive coup", "Third World bullspombleprofglidnoctobuns", "Partisan witch hunt", "dark day for our republic" and "Gestapo". Gee, some poor person literally getting their door kicked in or hauled out of their car window are supposed to be compliant and not complain. Now we know who the marshmallows really are.