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Quintessence of the speech was: without him there would not be a single war on the whole planet right now. But all wars there are these days are the result of Biden's political decisions.

But he also often leaves the political arena and pulls as many private issues into it as possible. Ad hominem attacks are one of his major rhetorical devices.
I don't know how serious Trump is when he talk about himself as a kind of global peace maker which would end all those conflicts easily. I doubt he is talking without knowing anything about geopolitics, because he was president of his country after all.
It is quite a interesting thing if you pay attention, he has mixed his propaganda of America First, but at the same time he has managed to continue to talk about conflicts from all around the globe. If he talks about making peace, then it is still a sort of USA mediation or interference.
Economically he wants to keep USA in his priorities, but politically he is similar enough to his predecessors in the White House. They may even have a quite similar definition on what peace is.
I think he's a better negotiator than Biden so he may be right about no wars right now if he was still the POTUS. You can probably look at Kim Jong Un's crossing of the South Korea border during Trump's admin and normalization of relations in the middle east as an example. He may still continue the US influence or presence in other countries but I doubt he would escalate things. He understands that it would cost more for the American people if wars actually broke out.