The social-democratic party of Germany (SPD) will soon have a new chairman and candidate for chancellorship. Parties are required by the German constitution (basic law) to follow principles of democracy (Art.21(1)). This requires them to elect a chairman if there is such a party office, but in SPD, CDU, CSU, FDP and maybe even Die Linke and the greens this is a mere theory. Party offices get distributed by "top" politicians, and the low-ranking party members are supposed to elect the chosen one in an uncontested election. The question is merely how many do so. 80% is considered to be a signal of distrust by the party base, and anything up to about 90% gets widely interpreted as a signal that the politician did anger the party base in some way.
That's not exactly a description of democratic inner workings of parties, and may very well be a reason for why they are hardly able to adapt and reform; the small clique of "top" politicians have all the power, and any real party reform would have to begin with removing them. They don't remove themselves, though - biology does. They only rotate offices between themselves. The SPD chairman of the past years is now supposed to become minister of foreign affairs, without having any noteworthy competence in this field. But that's no obstacle - after all, he had no particular competence to show for his current government office (minister of economic affairs) either. Everyone seems to assume that he wants the other office because politicians usually get popular and liked in it.
OK, that was the civil liberties and democracy ("freedom" ) part. Now let's look at the "defence" part of the story:
The pre-determined next chairman is Martin Schulz, a career politician known for his chairmanship at the EU parliament. He's part of the party's right wing, and this means a lot, since the party has shed its left wing (it deserted to the party Die Linke) a decade ago as a consequence of the non-social democratic policies under the SPD's right wing chairman Schröder. He's right wing in a party that consists of what used to be its right wing, and they're in a governing coalition with a slightly more right wing conservative party, the CDU. So the SPD is practically guaranteed to not turn to the left any time soon, but rather to become even more similar to the CDU. I strongly suspect that this is idiotic politics, for it practically guarantees an election defeat. Nobody needs a SPD that's hardly distinguishable from the CDU.
Moreover, Schulz is a European unification ideologist. Such people - let's call them "EUIs" - are extremists in their preference for international cooperation with all but a handful bad guy states.* Many EUI politicians also seem to be hawks regarding the bad guy states, eager to get the EU and/or NATO to bomb some other country together. Emphasis on "together" - that's more important to the EUIs than the bombs themselves. Their ideology is bipolar - cooperate and nothing but cooperation among friends and people you want to be friends with, including cooperation in extreme confrontation against people they feel no sympathy for.
So in the - incredibly unlikely if not impossible - case that the SPD wins the next election and leads a governing coalition with Schulz as chancellor we could expect to see almost no noteworthy reforms in domestic policies, but a lot of the EUI agenda in action. It's a bit difficult to predict an interaction of EUIs with Drumpf, though. On the one hand EUIs are "Transatlantiker" (preferring European-American harmony and cooperation), but on the other hand they're so only if it's not at the expense of the EU, and Drumpf is known to dislike the EU (and presumably all international win-win cooperation).
Meanwhile, the official German conservatives (CDU and CSU, politically ~ New England "liberals" and Texan "liberals") will have to decide how to fend off the attacks by the anti-internationalistic AfD, which is somewhat anti-EU (at least anti-Euro currency) and somewhat xenophobic, with an obvious infiltration by those closet neonazis who never quite joined the obvious neonazi parties. This may change the EU-related and immigration-related policies of the official conservative parties.
So what's in all of this regarding common "security" policy or common "defence" policy of the EU?
In any case the only EU nuclear power left is France, and they'll have their own presidential election. It's unlikely that much of anything in regard to the EU happens in France until that election, and if Le Pen wins the presidency there might even be an unofficial 'Franxit' - with the French government likely being unable to leave the EU, but wholly able to bring it to a full stop.
Let's assume that the French conservatives win the election instead, and so do the German ones. I suppose in that case everything is possible in regard to further European unification efforts, but most likely those policies will happen early on that were so far blocked mostly or only by the UK.
I don't think there will be real EU army prior to 2030, though. Maybe some symbolic 'EU rapid reaction corps' nonsense, but hardly anything real.
One thing might be feasible due to Drumpf, though; we Europeans might kick the Americans out of SHAPE and reinvent it as a wholly European headquarters, with Americans, Canadians and maybe even British officers as mere liaison officers. That might be politically feasible, fairly simple organisationally and almost for free. I doubt it would happen without Drumpf withdrawing or announcing to withdraw all American forces from Europe, though.
*: I dislike their almost perfect inability to admit design faults, overreach and other imperfections of the EU or other European unification projects. The marginal inability to correct mistakes is the single biggest problem in the EU and the Euro currency. Well, to be fair, the Euro currency in itself is a design fault and a result of EUI dreaming that perfectly disregarded the economic theory of the optimum currency area as well as all economic history lessons about the devastating fixed exchange rate regimes..