Read it again:
Add to these the Communistic groups who were opposed to intervention until a few weeks ago, and I believe I have named the major war agitators in this country.
I didn't read it as particularly antisemitic, at least not openly and violently so. He does not seem to treat Jews any worse than "the British". I saw no particular hostility to Jews, just opposition to a cause favored by most Jews. Again, you citation, in more context:
It is not difficult to understand why Jewish people desire the overthrow of Nazi Germany. The persecution they suffered in Germany would be sufficient to make bitter enemies of any race.That last paragraph could be more clear. I didn't see it as threat, maybe a misdirected warning. I wasn't sure if it was intended to warn of consequences to German or American Jews. Pearl Harbor, or no Pearl Harbor, the brunt of the task of defeating Germany fell to Russia. Without Russian success, which was by no means assured in 1941, the War in Europe would have at best been a tie. If Japan had helped Germany finish off Russia, she could have had easy pickings in Siberia, and a strong ally against the United States.No person with a sense of the dignity of mankind can condone the persecution of the Jewish race in Germany. But no person of honesty and vision can look on their pro-war policy here today without seeing the dangers involved in such a policy both for us and for them. Instead of agitating for war, the Jewish groups in this country should be opposing it in every possible way for they will be among the first to feel its consequences.
Tolerance is a virtue that depends upon peace and strength. History shows that it cannot survive war and devastations. A few far-sighted Jewish people realize this and stand opposed to intervention. But the majority still do not.
The paragraph after your last quoted paragraph reads:
Their greatest danger to this country lies in their large ownership and influence in our motion pictures, our press, our radio and our government.
That's a well-worn antisemitic slur.
Lindbergh was racist and anti-Semitic, although this was relatively common among Americans at the time. Of Swedish ancestry himself, he believed that northern Europeans were racially superior. His admiration for the Nazis was quite real. He developed a disgust for democracy after the chaos of the kidnapping-murder of his son, and the sensational Hauptmann trial.